I've seen self-checkout lanes that are for Walmart+ members only, but I never bothered to look into the program.
I never liked Walmart before they opened one very close to me in Frisco. It is always clean, the meats and produce are usually very nice (better than Kroger), and there are dozens of Mercedes, BMWs and Audis in the parking lot, along with the "beaters" one might expect to see. At any given moment, you could have someone with a Platinum credit card checking out next to someone using a SNAP card (formerly know as food stamps) -- and everyone is comfortable with that.
I popped into a Walmart in Houston once, and there was an
armed security guard in the front of the store.
Another reason I refuse to move to Houston where my family lives.
CD