I've suggested a different take on PNBL in the context of gambling before, to protect people against addiction without outright making it illegal as is widely done today. The idea is if you want to gamble more than some unprotected quantity, you have to first allocate the money and leave it for a month or two. People with insufficient impulse control or financial security will find that hard, but light recreational users shouldn't be inconvenienced too much.

The same ideas can work for other things, though it's easiest to apply to predatory behaviour.