I suspect part of it is overall societal changes pertaining to phone usage. When I was an elementary school student, I carried a few coins in the event that I

I suspect part of it is overall societal changes pertaining to phone usage. When I was an elementary school student, I carried a few coins in the event that I had to call someone on a payphone. (Which happened very rarely.) But today, we have no payphones. Well, almost none. So what else could you do, with no payphone? Perhaps you could find someone else who had a phone that they could let you borrow. In years past, it wouldn't have been that uncommon to walk into a store or other place of business, or walk into your school office, and politely ask if you could use the phone. They might let you, or they might not, but it was a reasonable request. I imagine today that it would come across a lot more suspicious. Why don't you have your own phone? Both infrastructure and ways of thinking have shifted toward assuming that all individual people who might need to make a phone call have their own personal mobile phone. Children being assumed to have their own phone is probably more of a grey area, but even so, things have changed, and there may be no going back.