Barry Bonds has absolutely no reason to continue to take the abuse he would no doubt have faced at every single park except AT&T. He has no records left to chase. Unless he's stupider than anyone can possibly imagine, he'd have to lay off performance enhancers completely because getting caught would just seal the already-nailed coffin. He has squillions of dollars and, I would imagine, a pretty comfortable life away from baseball.
So if came back making $2 million for any reason whatsoever, yes, I'd have a very small bit of respect for him. Sorry that doesn't make sense to you.
Look, I have great respect for people who continue to pursue what they love or what they're good at even after their original goals have been either surpassed or buried. I think augmenting your goals is a sign of maturity and love for what you do. At some point we all face the reality that we will never be physically what we were at 20, that we don't fulfill society's expectations of beauty past 25, that our best and sharpest work may be done at 30 or 40 or 50. It is the good ones who step back and say, well, I'm going to do my own thing now, and it may not make sense by standards of records or money, but it's good for me. If Ken Griffey Jr. really had called it quits when his best years were over, he would have stopped playing after 2000. He's already made it clear that being the best isn't the most important thing anymore, and so his wanting to play more is in no way inconsistent with what we've witnessed for the past eight years.