I get it, I'm a smoker. Sometimes there's no garbage can or ashtray around. In fact, with city cutbacks, it seems there are fewer and fewer.
But that doesn't give you an excuse to toss your cigarette buts out on the street or on my front step. Field strip the damned thing, tuck it in your pack and throw it away. Not only are you keeping the streets looking nice, you're also saving it from being washed into the drains and into the river. It isn't hard and if you're not doing it, you're a lazy fuck.
Have some pride in where you live/where you're visiting just for once.