Most everyone knows the Merc, one of the most iconic structures in the downtown Dallas skyline with its mid-century clock and steeple.

But unless you live in one of the residences there or know someone who does, you might not have had a reason to visit the 31-story Art Deco beauty – but if you're looking for groceries downtown, you suddenly have a reason to stop by.

Royal Blue Grocery opened its doors Saturday for a soft open in the bottom floor of the former Mercantile Bank Building at 1800 Main St., fulfilling a need that had largely gone unmet in the Central Business District — an actual, full-service grocery store.

One with luxurious hours, too.

The beautiful space still had temporary elements during its opening weekend. The wine looked like it wasn’t yet in its permanent home, the TacoDeli breakfast tacos went quickly and an employee was still slapping price stickers on things.

Saturday saw a rush of people, while Sunday morning offered a quieter vibe with fewer customers, one of whom was bugging employees to help her find quinoa. By midday, the place was full again.

“The neighborhood’s enthusiasm for us, needing groceries downtown, was really inspiring,” says Royal Blue Grocery managing partner Zac Porter. “Everybody had really nice things to say even though we’re about 40 percent stocked with inventory. ... We normally take four or five days to stock ... but the neighborhood was excited, so we wanted to get it open.”

EXPAND The new Royal Blue Grocery is open 7 a.m.-10 p.m. daily. Taylor Adams

Both days featured groups of people walking in just taking a look at what’s inside, gawking at routine items like fresh broccoli.

Royal Blue Grocery joins a growing list of welcome additions in and around the Central Business District, like the Commissary, which offers well-executed meals and a few items for the kitchen within walking distance for many residents.

And now there’s a grocery store, something every neighborhood needs. Mind you, this is probably not your main stop for your weekly grocery haul — you still might have to drive for that. Deals aren’t Royal Blue Grocery’s thing.

A downtown Dallas Facebook group was flooded with posts this weekend from people disappointed by — and defending — Royal Blue's prices. "Wow. Just wow. $6.50 for a gallon of reg whole milk non organic," one user posted. "$5.50 for a cup an[d] a half of watermelon. $15 bucks for a jar of pasta sauce. Well Royal Blue, at those prices it’s not [worth] paying to just take a elevator downstairs. 3-4x the price as Tom Thumb an even 2x the price as Whole Foods."

"Crazy expensive. Ridiculously overpriced," another user wrote. "$4 for rosemary herbs that cost half that even at Whole Paycheck. Wine is unbelievably marked up as well. We are all paying for convenience. Produce section is barely a produce section. I was so excited but am now deeply disappointed. The space is tiny. And it really doesn’t fix our need for a grocery store."

But Royal Blue, which also has a location in Highland Park Village, has always been a high-end grocer, and the fact that there is a produce section, a few fully stocked aisles and a selection of prepared foods in downtown is a big deal for the neighborhood. It’s exciting to be able to run over here when you need another vegetable for dinner, a bouquet of flowers or to indulge in a new brand of chips for late-night snacking.

EXPAND The downtown Royal Blue also sells premade foods. Taylor Adams

And the store’s generous operating hours — from 7 a.m. to 10 p.m. every day — make those spontaneous late-night runs almost too tempting.

“We’re a fancy-looking grocery store because we’re trying to be modern and current for the neighborhoods that we’re in, but it’s an old-school model,” Porter says. “We carry what the neighborhood wants ... If the neighborhood wants Campbell’s Soup and Frito-Lay and Diet Coke, we got it. If they’re looking for a kale salad and kombucha, we’ve got that, too.

“We try to make our best guess for what we should stock to serve the community ... and we ask for requests and listen real closely to what people are looking for.”

The coffee bar serves drinks using Stumptown Roasters’ beans, and there’s a lovely, L-shaped seating area for people to share a coffee date or eat one of the prepared foods. In the morning, there are tacos: Some are TacoDeli, others are prepared in-house.

It’s a decent working place, too, unless you need WiFi. But is it such a bad idea to disconnect for a little while?

“We wanted people to talk with their neighbors and colleagues, chat and meet people they haven’t met before,” Porter says. “I’ve observed when the laptop crowd shows up, they put on their headphones and get in the zone. And all of a sudden, we have a library and not a restaurant.”

Porter remains here as managing partner, while the founding partners call Austin home. He runs it along with his wife, Emily Ray-Porter, and his best friend, Cullen Potts.

While the Highland Park Village location opened three years ago, there isn’t really a Park Cities vibe at Main and Ervay. Porter’s team started looking downtown well before Highland Park was considered — the latter opportunity just came along first.

“We may have been a little late, but we’re here now,” Porter says. “I think our location is a ‘main and main intersection.’ We could argue this is the bull’s-eye of downtown.”

Walk in to this fancy, little grocery store, and you’ll see a line of carrara, two-top tables to the side next to the coffee bar. Head in the other direction, and you’ll find the groceries.

“Before we got here, you were kind of limited to apples and bananas from a convenience store, not produce that you cook with,” Porter says. “We got a lot of snack foods, people can grab food on the run; then we’ve got pantry staples, things to make entrees and dinners with. We’ve got ingredients for your recipes.”

EXPAND The new downtown grocer sells wine, too. Taylor Adams

One sight has great potential to rev up excitement: an island case of fresh vegetables. Porter says another is on the way, which means even more produce.

Beyond that are a few aisles of pantry goods, ranging from everyday chips to products from smaller labels. The grocer sells honey butter and fresh eggs from South Dallas' Bonton Farms. In the back is a small display of baked goods and another island featuring cheeses and prepared foods.

Music from Porter’s own Spotify playlist supplies the ambiance, offering a calm feeling quiet enough to inspire good conversation.

A few things are still on Porter’s waiting list: a freezer for more frozen options, chairs to go with the two-top tables and a little bar that will offer seating against the westward-facing window.

Porter says he’d like to add outdoor seating one day.

The design elements reflect the brand of Royal Blue: a cool green paint that complements the deep blue of the brand, sleek carrara marble and modern lines. Natural light fills the space with large windows along the outward facing walls.

“We had all these great windows — that was fun to play with,” Porter says. “Most grocery stores have no windows so they can fit more product. We’ll sacrifice the merchandise space for a pretty room.”

The Merc itself served as a design inspiration, Porter says.

“The Mercantile’s Art Deco started off as a jumping-off space for things like curved counters, mid-century fixtures, lots of brass mixed in,” he says.

All he needs to embrace the vibe further is mosaics on the wall. But bring that up and he’ll say Royal Blue is working alongside Forest City (which manages area properties) and Page Southerland Page (an architecture and design firm next door) to make a mosaic on the sidewalk, featuring the clock tower that essentially is the identity of the former bank building.

There’s been a call for groceries downtown for years. Urban Market two streets over sort of, kind of, filled that need before it went out of business a few years back. And while some may scoff at the ritziness of this business, they should remember that at least this fancy little grocery store is making an effort.

“We’re super excited to be here,” Porter says. “The reception was really pretty heart-warming. And we’re just a third of the way there.”

Royal Blue Grocery, 1800 Main St. (Downtown). Open 7 a.m.-10 p.m. daily.