And the elephant in this conversation is the tendency of the beer community to not support macro-brew.
I think this mentality is less true than it is believed to be. On the whole, my friends who drink craft beer still drink macro beer. I can't think of any who don't from to to time, the more I think on it. But most of my friends aren't diehard beer geeks, they just enjoy finding good beer and socializing.
It's always important to point out that not all macro beer is hostile to the craft side of the industry. Guinness is an excellent example, they've done a lot try and improve MD beer laws for the small guys. The only macro I personally avoid is inbev, due to their pretty hostile stance to homebrewing not too long ago. However, if that changes and they play nice, I'll buy their products again.
I think another reason most folks who like craft beer buy macro is there isn't a similar product available from the craft guys. Just try and find a non-Guinness stout under 5% abv for example. Heck, just try finding any sessionable craft beer that's actually drinkable at this point. (Besides Yuengling and Sam Adams, I don't know of any good under 5% craft beer...at least in my area.)