Is There A Such Thing As Being Too Old To Sit On Mom’s Lap?

A girl never stops needing their mom throughout their life but is there such thing as being too old to sit on your mom’s lap? Well, at Walmart, the answer is yes because the motorized carts are meant for only one person.
Obviously, the girl looks capable of walking, so why isn’t she? In addition, if she couldn’t or didn’t want to walk, why not just grab another motorized cart? I would think this would make shopping very difficult because she can’t even see where she is going.