In my experience it is a company culture kind of thing. I have worked at companies where managers with kids are leading the weekly beer bash, and I have also been at places where there are multiple kegerators that no one ever touches.

Once I heard it was an AA strategy for ex-alcoholics: just say you can't drink today. You'll suffer no pressure to do it.

I get reactions too, it's usually "meh".

Then again, I live in an area where you're more likely to catch flak for drinking then not.