The long lines at Trader Joe’s are there for a reason: It’s America’s favorite grocery store.

For the third straight year, Monrovia, Calif.–based Trader Joe’s, known for its Hawaiian-shirt-clad staff and a variety of cultishly popular products, ranked as the country’s favorite grocer, in terms of both customer satisfaction and the percentage of customers saying they’d be likely to recommend it, according to a survey of more than 7,200 consumers by the research and consulting firm Market Force Information, which counts major grocers including Trader Joe’s sibling Aldi among its clients. It said respondents represented four U.S. census regions.

Lakeland, Fla.-based Publix, which said it’s the largest employee-owned grocer in the U.S. with $30.6 billion in 2014 sales, ranked close behind Trader Joe’s. Aldi, the discount chain headquartered in Essen, Germany, came in third place.

Respondents had a list of almost 100 grocery-store brands with at least 200 locations each to choose among. The final ranking includes the 14 brands with 2% or more of respondents considering them their primary grocers. By that metric, Wal-Mart Stores Inc. WMT, -1.02% was the least favorite in the final tally, trailing on measures from items in stock to checkout speed.

See:How Wal-Mart wants to bring former shoppers back

That’s despite the fact that Wal-Mart is the largest U.S. grocer by market share, according to a Euromonitor study for MarketWatch. Publix, according to that study, is No. 4 , while Trader Joe’s ranks 12th and Aldi is No. 14.

In the Market Force study, when it comes to the question of value, Trader Joe’s ranked No. 4, behind Aldi, employee-owned and Boise, Idaho–based WinCo Foods, Costco COST, -0.86% and the Wal-Mart’s warehouse chain Sam’s Club. ShopRite scored highest when it came to the question of having “good sales and promotions.” Publix ranked No. 1 for measures including having product in stock and ease of finding items. Trader Joe’s ranked No. 1 for cashier courtesy.

Whole Foods Market Inc. US:WFM , which recently said it’s opening a lower-cost chain to target millennials, missed the list for a second straight year after being ranked No. 3 in 2013. The reason, Market Force Chief Strategy Officer Cheryl Flink told MarketWatch, was that it was not ranked as primary grocery store by a sufficient number of survey respondents. If it had cleared that bar, Flink said, Whole Foods would have ranked behind only Trader Joe’s and Publix as a customer favorite.

“What Trader Joe’s is known for is a different position,” Flink said. “They have interesting and unique merchandise. Their brand is very different. People can say, ‘I can go to Trader Joe’s to find things that I can’t find anywhere else.’ ”

With Publix, she said the company has “put its stamp” in the Southeast and has placed emphasis on customer service and employee training.

Other findings:

• Nearly half of respondentssaid they prefer to buy organic products, with produce, meat and dairy the most purchased organic items.

• 28% of consumers said they are buying prepared mealsat least once a week, a 10% increase from 2014, in a sign that supermarkets are increasingly competing directly against quick service and fast-casual restaurants by offering more prepared meals and gourmet options, the study showed.

• Click and collect. The study also showed while retailers including Wal-Mart, Target Corp. TGT, +0.82% and Kroger Co. KR, +2.15% offer an online-order option with store pickup, only 5% of respondents said they’ve bought groceries using that service. Sam’s Club saw the highest usage among the respondents.

• Retailers need to promote their apps better. The study found 61% of respondents saying they’ve never used a grocery app, while 23% said they’ve used a specific grocer’s app. Among those who’ve used grocery apps, 72% said they use them to get coupons, while only 19% said they use them to compare prices among multiple stores.

• Print fliers still matter, with 86% of respondents saying they review a weekly printed circular at least once a week to find grocery deals.