It seems like I agree with most: as long as it's responsible drinking, not falling down drunk, no problem whatsoever. It makes no difference if it's at WDW, the state fair, sporting events, etc., I don't want to see highly intoxicated people or have my kids see them.
Personally, I would need a nap if I drank during the day while visiting the parks, but I certainly would like the option to have a drink with dinner regardless of which park I'm visiting.
I guess the only good part about heavy drinkers at WDW is that most of them probably aren't jumping in a car and driving afterwards and there are plenty of CMs and security personnel around to deal with them.