My assumption is that one can have a drink or two without it affecting him the way a smoking pot would. That's a bare bones thought.
I'm no expert on this matter though. I tend to observe these threads from afar, let the people who are used to debating it be without my messing around. :)
I'd rather ride in a car driven by someone who just had two hits off a bong than I would someone who just drank two martinis.