You do realize that the prices in the store right now are already the maximum the stores can charge, do you not?

Corporations are soulless and greedy. They don't set their prices by buying from a supplier and increasing them by a fixed percentage. There is no point where a company will go, "well, we could charge more and still have the product sell, but that would be improper." They already set their prices to the maximum the market will bear. They cannot raise prices further without a net loss of income. They set their prices for the maximum product sales cost and quantity sold.

And why can't the elderly or disabled use self-checkout? If you're capable enough to walk through a store and grab items from shelves, you're capable enough to slide them past a scanner. If they're shopping with a caretaker, then the caretaker can run the check-out instead. The level of dexterity required to use a self-checkout is the same as needed to grab items from shelves, inspect and bag produce, etc. Sure, some people are too disabled to use a self-checkout, but those folks are also too disabled to shop for themselves at all. That was literally how these systems were designed. The companies didn't want to have to deal with scores of people who were dexterous enough to shop, but not dexterous enough to run the self-checkout.

And why do you figure you can't write a law to accommodate that as well? Some of you guys are looking for so many nits to pick that you think it would be impossible to ever write a law regulating anything whatsoever.