I would never shop at a store like that
Walmart is one of very few grocery stores that doesn't have 2 sets of prices. Most of the major grocery chains have some sort of "VIP" card that you have to use to get the lower of the 2 prices. This allows these stores to track every purchase you make. Walmart doesn't do that: They are a much less creepy grocery store, IMO.
If they do it you won’t know you are. It’ll look like a regular cart. It’s a big data world, privacy is dead, you are nothing but data points, get over it. Railing against this is like being angry at the sun rising in the East: 100% pointless.