A majority of academics are in the pursuit of knowledge and furthering their respective fields. When you are working for a company a majority of the time you are doing something that does not further the field of science and knowledge.
As a former 2 pack a day smoker who thought "I can quit anytime" I'll tell you its not quite as easy as all that, it took a few times (as in 5 or 6) trying to quit to actually quit. In the end I found Chantix helped me quite a bit to kick the habit, for those that are curious I smoked heavily for about 12 years.