THis is one advantage of a pay-as-you-go phone. The phone only has so much money, and then it has to “top up”, and while that is “automatic”, it can only happen with a notification to the phone, which means the user knows they are getting hit with charges. So while my kids have accidentally activated services which generated daily charges, we never lost more than $15 or so.
And if I want, I can disable the auto-topups, so we have to take action to recharge the phones.
Cricket offers reasonably priced unlimited plans. This works for both consumer and provider. The consumer gets all the use they want and Cricket eliminates an entire department of people whose jobs would be to deal with unhappy customers who have been charged for exceeding their limits.