i dont get the not remembering thing... the worst i have been is not being able to work drunk, not being able to get up, throwing up a lot... and i could still think reasonably. i can remember a fair bit of that, its not like i'd get with some ugly chick like some guys do after very little alcohol.
as for the lightweights, or the VERY occasional drinkers they don't know what to expect. at my formal me and the usuals drank heaps, had a blast, but then sobered up. one other guy drank about a third of what we did and was completely gone, he was doing stuff that he would never do sober, so i guess that was his outlet/excuse. another guy was acting stoned off very little to drink too. they don't get what it does, and just pretend they are drunk. when you think about it, its not hard to act sober if you haven't drunk much, even though your not (so don't drive!)