I feel the same way at conferences, and I actually do drink, though I never binge drink.

But, that's not why I came to the conference. I can drink at home.

I think you're fighting a losing battle, though, because the demographic that is generally involved in programming is essentially the same (with a slight tendency to nerdy and aspie) as the demographic of bros, and going to a conference is like a paid vacation for people who like programming (and aren't too intensely on call) - hence party time. Think state college spring break.

I think social awkwardness has an effect, too. I'd venture to say that the computer obsessed tend to more socially awkward, and alcohol offers a crutch when attempting to consciously network.