Publix is also on that first list, of happy and overstaffed and privately owned. I do most of my shopping there and it's much more pleasurable than Kroger or Walmart.
Personally I hated Publix when I lived in Florida and it made me homesick. I've never had so much food come with mold in the packaging than from Publix.
While the employees might be happy at Publix, they are in, in my experience, poorly trained. Also, the rest of the shopping experience is utter crap compared to H-E-B. Publix of 2026 is a far cry from Publix of ~2000. This is especially evident in their Produce and Meat departments.
I had to argue with a Meat Department Manager at a Publix in Central Florida who told me that "Top Round Roast" did not exist. I told him I could walk 50 feet to the Deli and get some slices of the Boar's Head Top Round Roast Beef if he'd like to try this non-existent cut. He did not have an answer and I had to show him images of the cut I wanted and he said they don't sell that cut.
This was great given it was a 20-mile round trip to that store for me...
Having spent most of my life in the south, I thought Publix was a great grocery store. But then I spent some time traveling the US and discovered stores like H-E-B, Hy-Vee, Wegmans, and Harmons and realized that Publix was just clean version of a low-end grocery store.