Let me tell you why exactly it is hard to quit smoking or drugs:

First of all in our brains we have a dedicated organ to produce Nicotine in small amounts. Nicotine is needed to keep the body going when you are lethargic or to increase blood flow.
When you smoke or take drugs, you have excess intake of Nicotine. As you continue taking that chemical as foreign material, aftera short time the brain organ reduces its production of Nicotine, and over a period of time, finally it stops producing it. By this time since the brain stops production of basic required amount of Nicotine,( however we do need a certain amount for the body to function properly) we have to take Nicotine as external material.
We continue doing that and as the organ does not have any function left, it slowly dies making us even more dependent on Nicotine.
Therefore it seems hard to leave it, the effects of trying to leave it are-
1) Continous Headache.
2) Lethargy
You tend to take too much Cofee or tea to make up for Smoking.
The correct way to leave smoking is to leave it slowly.
1)Do not leave it all at once.
2)Reduce the amount of Cigratte you take every day slowly ( go by # of puffs every day). Do not reduce it to one less from previous day, instead you may stick to say half a cigratte less a day for a week or so and then reduce it by half again for a week.
3)Try to chew something which do not contain Nicotine when you really feel like having a puff.

Hope this helps, I was a smoker once, I left it with aid of any one else, I have been reading books and consulting doctors on the effects and after effects of smoking. I do want everyone I know to leave it slowly and with their own will.

Join me for the campaign against smoking( Not smokers)

You're right, Guest. Anything in excess is bad. The only difference is that eating fried foods in small amounts every day won't permanently injure your body or harm others like smoking will.

You're right about the buffet's, though. I'm not one to judge, but I know for a fact that lots of the people who go to those buffets are addicted to food and eating...otherwise, they wouldn't be 300 pounds. Addiction in any form is hard to break.