I think the main reason for kicking caffeine is the inconvenience.
For many years, I drank between 6-8 Coke-a-Colas per day. Caffeine addiction? You bet!
Whenever I travelled, we had to carry a cooler of Coke, because I was never sure that I could get it. If I went to a professional or religious conference or to an ice skating competition, that cooler had to be in the car with me so that during breaks, I could run out and get my Coke. Same for work–I had to bring a couple of Cokes to work for breaks, lunch, etc.
Needless to say, this got rather expensive. I always made excuses for not having a lot of money to give to the church–well–giving up Coke would have provided me with about $25/week.
Ignore the obvious weight gain problems. It was the caffeine that stopped me from quitting. Whenever I missed my Coke dose, I got a headache, along with the other symptoms of withdrawal–sleepy, grumpy, not alert, sometimes even a little disoriented. So I kept drinking the stuff.
Finally I got sick, a bad sinus infection. For two weeks, I didn’t eat or drink much of anything, let alone Coke, which you DO NOT want to throw up if you sick. THAT broke the addiction. I never went back to Coke. I’ve been Coke-free for about three years now.
It feels good. And I have money to give away.
And shortly after that, my husband and I became Catholic, and for the first time in my life, I was confronted with the teachings about abstinence and denial of the flesh. Oh, my! I’d never thought about denying myself any good thing! This played a major factor in my continuning to deny myself a Coke. I figured it was good for my soul.
Anyway, I think that the dependency upon caffeine is a good reason to quit. Consider what would happen if you were called to travel to a foreign country, perhaps to help out with a disaster like the tsunami. Here you would be on the plane or in your little hut suffering with caffeine withdrawal and unable to rouse yourself to help all the other aid workers! How humiliating!
Or what if you were attending some wonderful Catholic conference and they DIDN"t have anything with caffeine, and you forgot your stash. You would have to leave, wouldn’t you, just to get your fix? You would miss a great speaker or singer, just so you could constrict your blood vessels! Again, isn’t that humiliating to think about, that you would actually walk away from a great opportunity to serve God and learn more of His ways for the sake of a drug?