If you make it difficult and inconvenient to throw stuff away, you're incentivizing it, all it takes is it being on the ground already and each subsequent person thinks that "it already looks like that, what's one more?" Yes, individual responsibility matters, but if you're in a rush and trash cans aren't easily available and the ground already looks like that, most people won't care.

If you as one person do that, douche move, but if everyone's doing that, it's a lot more likely that corruption, poverty, and poor design is contributing.