3) Is there any particularly interesting analysis of why drinking is so important to social interaction? Knowing the underlying causes might at least give me some better appreciation for why I have to learn this other than "because!"

The last time I was drunk I told a non-drinking friend of mine in fairly loud and forceful terms that he should drink too. So let me try to introspect on why I might have done that.

You didn't mention anything about experiencing lower inhibitions while drunk, and feeling more willing to do stuff like dance, loudly speak your mind on anything, etc. I think this could be a big part of why my drunk self is upset when other people don't drink--I'd like them to share this low-inhibition state with me. For one thing, I'll trust them more. This might somehow be related to people speaking their mind more naturally when drunk--if I know someone is speaking their mind to me and isn't lying or leaving things out when they talk then that's kind of a bonding experience.

But a more important factor is probably that I want to see people who normally seem fairly straight-laced behave in crazy ways, perhaps because it would lower their status, or maybe so we can share the kinship of being crazy, or so that I can know that just like me they sometimes break social conventions, take off their mask of good behavior, etc.

For what it's worth, I'm in college, I like experiencing the disorienting effects of alcohol, I somewhat like observing my speech becoming slurred (although the thrill of that may wear off) and your thoughts about the taste closely parallel mine. Oh yeah, and I enter an interesting and fairly fluid mode of socializing and ideas come differently while drunk, but those don't have anything to do with my being upset at people who don't drink.