We're having an open bar at our reception. A good friend, let's call him Sammy, is a [functioning] alcoholic. He went to his best friend's wedding a couple of weeks ago and when I asked how it was he just responded "I was f'n hammered all night, have no idea."
I'm wondering if I can instruct the bartender to only serve him beer, no hard liquor. If this is the case, I'd probably tell Sammy in advance. I think he would take it well; we're very honest with each other.
Is this rude? Are there other ways to handle it?
The open bar is not consumption-based; we're paying a flat fee, so it's unrelated to cost.