Well, I can only tell you from my experience it's because...

1. I was change averse.
2. I wouldn't change unless the pain of changing was less than the pain of not changing.
3. Consequences had nothing to do with my decision to change (all the yets listed had no impact on my decision to quit).
4. Forming new habits required work, determination, patience, and humility - all of which I didn't have or desire.
5. I was a salesman (to myself) selling ideas to a starving consumer (myself)...I wanted to believe I could drink normally or even just a little bit abnormally.
6. I loved alcohol and I still do, but that's not unlike loving someone that has died. You can still love them you just can't have them in your life anymore.
7. I battled the existence of God, until I was completely ready to accept that possibility...and I quickly found out it was much easier to believe in God, even if He doesn't exist than to constantly question His existance and worry about going to my grave, "wrong." (I have to chuckle at how funny and egotiscal I was, I had to be right to my grave - the very place being right wouldn't matter if I were right, but would matter tremendously if I were wrong - ah the grand plan is something).

At 33 years old, I'm glad I don't have to travel the path of "if I only drink beer, etc" it's okay...and I'm hopeful you will be too.

I hope you find peace soon, I'm just starting to find peace myself.

Take care.