Mott the Hoople
Sweet Jane
There are plenty of ways to "enforce" it. The easiest way is to make it cost a lot for the disposal of waste at the end of the system (i.e. the dump, landfill, etc. . . ) and then let the costs trickle through the system. If a gas station wants to provide trash disposal to its customers it can pay for it and make up the difference in its pricing.
I thought the nickel charge for the container was the enforcement?