Why do Nepalese pollute so much?

Nepalese do not respect their environment in general. There are water bottles in every place, chocolate wrappers, papers, etc. I have noticed many times that people just litter places unconsciously. Why do people just throw rubbish on roads, on tourist sites, etc? It’s such a small thing still people do not bother.

People often complain there is so much pollution but forget that they are part of the problem.