The difference (from what I remember from an NPR interview) is that cocaine is a drug that is used much less frequently (a few times a week) than nicotine (whic

The difference (from what I remember from an NPR interview) is that cocaine is a drug that is used much less frequently (a few times a week) than nicotine (which is used several times a day). Frequent use leads to the brain getting that much more frequent reinforcement of the drug.