Spence,
Come on, if the BB was going to dump his chips to the SB why wouldn't he just check after the flop? and let the SB bet and take it! Or better yet, make a bet and fold after the SB raises. Originally we were talking about the BB that forgot he was already in. If you want to kill his hand, go ahead, I just don't think it's good for customer relations. I will say that it is a good way to get your message across to those players that don't know what the hell is going on. Pay attention damn it!
Cheaters and chip dumpers are a little more sofisticated than folding when in for all bets.
I also do not agree with this being soft play. I think soft play violations originated when two or more players would "gang-up" or "put the squeeze" on a player, knock him out of the hand, and then the colluding players would check it to the river, or fold when the right partner steps out with a bet. Try to find the guys that are working together, not the new guy that makes a simple mistake.