I think the key here is an eliminated player. If someone lights you up with four or five shots, you know you're out, and you put your arm in the air and walk off. I don't think anyone is going to complain to hard about that.
Where it becomes a matter of safety, is when you walk off the field and some creep decides to give you the bonus ball. I'm not talking about a stray shot here, i'm talking about a sting of paint, strait at you.
I think the thing here is intent, it's up to the referee to decide if the offending player intended to shoot a player the he knew was eliminated.
Good clues that a player is being bonus balled? The player is in open ground, hand above head, is hit several times, or is simply out of bounds.
Example, at Campaign Cup, a player from Bushwackers gets shot out of the 50s on the tape, then gets up and walks back to the dead zone with his hand in the air, and about 5 feet out of bounds. Then one of the twats from Dynasty hoses him for a good five seconds (remember these guys shoot 10+ balls/second). The player being bonusballed, puts his gun behind his head to protect him self and somehow manages to walk off field.
The player was clearly eleminated, his arm band was off, his hand and gun were in the air, and he was out of bounds. I believe the penalty for this offence is that you get pulled. but the judge didn't even bother to try and stop Dynasty from doing this, let alone penalise the offending player? (diablo field, banzais marshalling?)
My point is, it's not about playing fair, or pissing people off, it's about safety.
It's easy to over shoot someone, but when you're playing you're protecting your self. When you're walking off the field, you don't have the benifit of cover, you're totaly venerable to the opposions paint, especially if your back is turned, and your head is exposed.
As a judge, your first concern is for the safety of the players, followed by the enforcing of fair play. If a judge thinks you're being unsafe, they have to make it safe, and if it means taking you off the field, then that's what it takes.