I don't smoke but I guess I'm one of those coffee addicts that you are talking about.
I simply can't wake up without it. Simple as that. If I don't force myself up to make a coffee, I'd prob be dead after 15mins or something like this. At least thats how I feel everytime I wake up.
Before I started to drink coffee as a wake up potion, I simply overslept like 4 or 5 times a week... There was barely a day where I was on time for school. Got in quite some trouble lol