When one of your friends keeps cracking a new beer when he still has some left in the last can. This is usually noticed the day after a party when someone is cleaning up and most of his cans are nearly half full.
"I drank like 40 fuckin' beers last night." "Fuck man, c'mon, you were Johnny-ing all god damn night."
"Last week at the G-10 i picked up so many half full cans. Someone around here was Johnny-ing those beers like a mother fucker."