I think it's fine if you succeed well in your daily job, or acheive good grades in school. It's also fine if you don't steal or rip people off to smoke.

I smoke every night, and I go to work 7 days a week, and bike 15km a day. I eat right and I feel great. I am no means a burn out. I used to be, but then I practiced self control and moderation of my use.