Some guys I know pull out their launcher at select games...it's more of a bazooka / air cannon type of afair.
It fires a bag of BBs at a time and there's a pretty lenthy safe MED. It's used as indirect fire (it's mostly used as a prop in very controlled circumstances). Feels like a 12g going off.
Their description of how it'll blast a 1" bolt clean through car doors sets the "it shouldn't be directly shot at anyone...don't leave it lying around for dummies" stage pretty clearly.
They don't bring it out very often for the reasons that it's use is often very limited (no-one really wants to be obliterated en-masse by a down pour of BB's from the sky)...and that it'd be very dangerous if an idiot got their hands on it. The usefulness/risk isn't worth the fun factor at general games.