Have you ever "repaired" your accidentally broken cigarettes with a piece of cellophane tape then forgot about the tape until you were inhaling burnt, melted tape as well as the tobacco? I did that almost everytime I broke a cigarette because I'm an addict.
Have you ever been at a party drinking soda or beer out of one can and using an empty can as an ashtray, then forgot which can was which? I have because I'm an addict.