I tried getting her a card, but none of the local banks would do it, and even the prepaid cards that you buy at supermarkets will not allow you to activate in your name unless you are a certain age. I finally found a card with FamZoo that worked for her, but it was way more difficult than it should have been finding a way for her to legally buy ice cream from that store.
I am paying closer attention when I go to a brick and mortar store these days, and I am seeing more and more signs advising customers that their cash is no good there.
This is a scourge that is starting to get out of control. My HOA advised me that I would only be able to pay them using a money transfer app. When I tried using it, it rejected my bank account information for some reason. I sent them a check with a letter explaining that their required method of payment didn't work for me. They didn't deposit the check, and then they tried charging me late fees. I had to go out of my way to escalate to resolve that.
This is getting to the point that we will need some regulation to protect the right to pay for ordinary things like ice cream and HOA dues with cash and checks.