---
"One of the floor’s tenants attempted to solve this problem by posting passive-aggressive notes on the paper-towel dispenser.
(Image of a paper with "Please discard paper towels into wastebasket." written on it)
The signs never worked. Instead, they just annoyed and angered people. Some people even threw more paper towels on the floor because they didn’t like the condescending way they were being instructed.
---
That message is anything but passive-aggressive. It's direct, reasonable and courteous. It's also very ordinary and I've seen signs like it in various public restrooms, train stations, subway stations and other areas. If someone is actually angered by this kind of sign and decides to litter more as a response, they're probably not a very easy person to get along with.
In many places, such as Singapore, Hong Kong, Taiwan, and much of east Asia, this problem is solved via fines. Over time the fines even change social norms about littering and the situation improves in areas without the fines. The analogy to copyright is pretty weak. Many places with more civilized norms in terms of litter really don't care about copyright infringement to the extent that English-speaking countries do. Copyright behavior has also been very resistant to being altered by fines.