Can't you, if he's not in any danger, just use him to prop up a sign saying "Ambulance already called to this drunk. He told us FUCK OFF. He wasn't in danger, so we left him here. If he stops snoring and can't manage another "FUCK OFF" when you poke his leg, feel free to call the ambulance for him again." It might make the sod embarrassed when he wakes up cold and hungover, plus leaves you guys free to do other more important things.