"and its a waste of money IMO since the work is going to get done wether the money is sent or not, is it not?? "
Not necessarily no, that being the point of the bounty projects.
Also, if people send money, the team are MUCH more likely to feel glowy and spend more time on it, meaning that it arrives much sooner and in much better shape (from the perspective of those paying) than it otherwise would. You pay me and you get to say "I'd like that feature" with a lot more conviction.
John