Seriously, you have lots more things to worry about when you're smoking than wrinkles around your mouth. People who smokes understand fully the risks by now right and if it's one your pleasure in life, it's your own choice and by all means enjoy it. If you want to live longer, break those bad habits. Not just because of those darn wrinkles.
Gosh, we have became a society of beauty and health freaks, the straws is a limit. Do not eat this, do not drink that, do not, and donuts ... Do any of us remember all those do nots when we were kids, all the stupid things we did ? And how much joy it was ?
If you keep watching everything out there, you'll stop enjoying life and become just a slave. Growing old is a part of life and no amount of care can keep you wrinkles free forever. Smiles a lot can cause wrinkles, but by all means enjoy it and forget about those little wrinkles. Enjoy those what you do, a few wrinkles from your smiles is like the holes in the fine cheese. Doesn't stop it from tasting good, au contraire.