Highways and roads as ashtrays

Here is a question. Note; this comes from the person behind you on a motorbike.....

Why do some motorists that smoke throw their 'still lit' butts out the window? Does your vehicle not have an ashtray? Use it!! And if its full, empty it into the appropriate garbage receptacle and not the parking lot at the mall.

The roads are not your ashtrays!!

This obviously falls under the 'frustration' column.