It's trivial
Lots of poor people have in residence electricity boxes that require prepayment for usage. In the olden days you put a coin in to turn on the power, but nowadays they have apps and digital payment solutions!
They might already have ads in those apps...
This is all news to me. It seems like it would be tough to prevent people from just using the power that's going to that box.
I guess I'm out of touch, because I've never heard of anything like this. I've had my power turned off for non-payment before, but I had to talk to someone at the utility to get it switched back on.