Of course you are right about W-Mart being cheaper then Publix. Always have been. But Publix is flourishing in Florida for a reason.
It's more then just comparing the price of a can of peas. Lots better selection and a real good deli and bakery (they make great birthday cakes). And they make the best store bought key lime pies in the state of Florida IMHO.
Also, there will usually be a clerk around if you need to ask a question.
I would have to be in the right frame of mind (strongly medicated !) to shop the Walmart in Homestead but I actually enjoy going into a Publix.
Like most things, you get what you pay for.