The problem is everything is a massive chain so as one goes, so goes them all so to speak. I have Kroger, Albertsons, and Walmart as my only choices for grocery store. I don’t see any chance that if Kroger does this Albertsons (assuming the proposed Kroger Albertsons merger fails) and Walmart don’t do the same.
Tl;dr it doesn’t need to benefit the customer if the customer has no real choice in where they shop
Many states have little to no rules on storage. You also don’t really need a license to buy one just to carry it concealed in public (some states don’t even require this step). Of the states that have storage laws like my own, I’m unaware of any that require you to prove safe storage though. The laws only offer a punishment after the fact when something bad happens.