Why can't smokers use an ash tray inside the vehicle?

If they can’t bring themselves to use the vehicles ashtray, then why not a dollar store one that hangs off the door or dash.
Mrs Squeeky said if that is too much then why not a pop can with a bit of sand or water in it, that would make a fine ash tray as well and you could just throw it in the trash when done.
I bring this up because we are experiencing one of the worst forest fire seasons ever here in B.C.
Main highway routs have been closed for weeks, several whole towns have had to be evacuated, and yet smokers still toss their butts out the window, why?