In my state (New York), horse-drawn carriages are included in the DWI statute, as well as bikes. Glad thing, too, since occasionally even the local Amish over-indulge and then hit the road. If a carriage driver is either drunk or unconcious, the horse will head home, but won't stop at intersections.
I guess what disturbs me most about your post is the way you seem to feel that it's acceptable to be operating anything when you are intoxicated. This is totally unacceptable, juvenile behaviour. If you are too d@mn drunk to walk, then sleep it off!
Yesterday, I happened to observe an intoxicated man on a bike, using the local multi-use path. It was bad enough that he was drunk, and that he was riding one-handed, with a beer can in the other hand, but he nearly ran over a small child while weaving his way through people. Eventually, he did a face-plant in the grass along the road, and I gladly joined in the laughter at his misfortune.