Rikkitic:
+1 to considerate smokers who do respect signs, in spite of there being so many, and do dispose of the butts correctly. Not every smoker is a neanderthal, and non-smokers leave a hell of lot more trash behind. Let us not stereotype and judge. Smokers are addicts, and they suffer when they can't get a hit. Condemn the bad ones, but show a little tolerance for the others.
If you are saying smokers don't leave other rubbish behind as *well* as butts, then I'm afraid you are just dead wrong.
Smokers aren't more considerate of their rubbish disposal than any others. The chances that they would dispose of their rubbish if they were prepared to leave butts behind isn't realistic.