They should make a sitting emote. You press it and you sit down on a bench. This would be for AFK-ness. When you use it, nothing will happen to you. It's like you're not there, but you won't get kicked.
I hate games that when you're out of ammo, you have to press "R" or click after you're out of ammo. This game, however, does not do that. THIS GAME IS BOSS!!!