At least for now, games are a purely audiovisual medium, which can be somewhat limiting. It’s difficult for studios to properly simulate less tangible effects… like, for instance, hitting the bar a little too hard during a night out in your favorite virtual city.
Most of the time, being drunk in games amounts to a visual filter, some mushier controls, and maybe a special voice line or two if you’re really lucky. As with any aspect of game-making, however, there are a few examples that manage to stand out and really place you in the shoes of someone who’s blown off saving the world to go get sloshed—although why you’d want to be there is anyone’s guess.