smokers!! i hate smokers!!

ish..one thing i dn't get, WHY DO PPL SMOKE?!
i'm sure by now everyone knows what are the effects of smoking.
IT CAN KILL YOU!! duh!!
but still, many ppl do it. can someone tell me why?
just today, i went to a family dinner, and sitting beside us were two tables filled with nasty smokers!
i can't stand it. They smoke and smoke and SMOKE!
i mean for their own sake, STOP TRYING TO KILL YOURSELF!
tar and nicotine is serioiusly bad for us.
Less smokers die from lung cancer than those who dn't smoke but was exsposed to the smoke!
That ain't fair.
So ppl, STOP SMOKING. IT'S BAD. REALLY BAD!
just hope my brother doesn't do the same.....