If Mark Davis had been at the Giants’ ballpark Thursday night for the opener of the Bay Bridge Series, he might have had a good laugh at the Giants’ expense.

The Giants’ ballpark, spiffed up and ready for its 18th season in the sun and moon and fog, looked as good as the day it opened in 2000, and the Giants, the team, also seem in great shape.

What chumps the Giants are. Two decades ago, after years of attempted civic panhandling and legal extortion, they broke all the rules and built their own damn ballpark.

Worse, they built it in the same little city that wouldn’t give them free money. They rewarded the fans who supported them through decades of mostly bad baseball played in wretched conditions.

And they stocked the team with real players.

Now, the Giants are stuck in a marvelous ballpark that is only better with age, backed by fans who Thursday treated a seventh-inning rally in a practice game like it was a key moment of a World Series.

The Raiders’ owner, were he at the game, would have laughed all the way back home to Las Vegas.

The Giants are so naive and cornball, like the teacher’s pet who brings the shiny apple every day. Thursday’s game was a reminder of how out of step the Giants are with the cool kids in class.

The 49ers built their stadium, good for them, but they abandoned the city that birthed and raised ’em, then they abandoned the head coach who helped build the stadium. Then they abandoned sound business principles.

The Warriors, hard to find fault with them. They’re building their own arena, but they, too, are moving out of a super-loyal town whose fans kept the franchise humming through two decades of bad ball. The old fans still can follow their players, with just a few extra miles of a commute, but those fans might need to take a second or third job to pay the jacked-up ticket prices.

The Raiders, of course, have done everything by the book. Make demands, threaten to move if your hometown won’t (or can’t) pony up half a billion or so for a new facility, then make good on your bluff — take your ball and go to a new home — far, far away.

The A’s? Well, they’re talking a good game. After years of using his team as an ATM, owner John Fisher is indicating he’s ready to build a ballpark in Oakland and actually spend money on ballplayers.

We’ll see. With the Raiders on the move, the A’s surely soon will announce plans for their new ballpark. If that happens, after years of dithering and trying to leave town, of kowtowing to then-commissioner Bud Selig, we’ll find out if Fisher is serious about playing big-league ball.

The Giants are so corny. They have a master plan. Draft smart, develop carefully, pay the going rate for good players and hang onto the players who develop into stars.

The A’s are light years from any type of plan like that. Already there is speculation about whom the A’s will unload this summer if the season doesn’t go well.

Stephen Vogt is on that list, the type of steady producer and leader you build a team around. Also on the list is Sonny Gray, if he can bounce back from injury. Remaining disabled might be Gray’s only chance of remaining an Athletic.

Can you imagine that the baseball world is anticipating that the Giants, if they fall off the pace this summer, will unload Buster Posey and Madison Bumgarner?

Once upon a time, the Giants were just like all the rest, with a hand out, happy feet ready to skip town, subjecting their fans to shabby treatment and a second-rate product.

So, they can’t feel too smug and self-righteous when they see Davis gleefully packing his bags and whistling “Viva, Las Vegas.” That was the Giants not so long ago.

But they saw the light. Otherwise, right about now, they would be hitting San Francisco up for a new ballyard. The place is pushing 20, which is 100 in dog-ballpark years.

Instead, the Giants have spit-and-polished their place, tucked into a nice corner of good old San Francisco. They’ve got a team that looks like it can play, stocked with players they’ve developed, or found and kept, like Hunter Pence and Johnny Cueto.

It’s still the place to be on a summer night. A million seagulls can’t be wrong, and most of the seagulls are veterans who started with the Giants here in 2000.

Scott Ostler is a San Francisco Chronicle columnist. Email: sostler@sfchronicle.com Twitter: @scottostler