I think everyone should take their new dog to obedience class regardless of how much experience in training they have. It's good socialization for the dog and a chance to teach them how to behave around other dogs. A lot of people say they'll work with their dog on their own but never get around to it. Going to class gives me that extra incentive to keep up with training at home. No one should be offended by being required to take their dog to one obedience class. They might even learn something new that could be helpful to them.
As far as paying for people to attend a class---forget it! Dogs are expensive. Food, treats, toys, vet bills, medication, etc. etc. If people aren't willing to spend a little extra money to take their dog to an obedience class they probably can't afford to have one to begin with. I'm sure BURN needs the money that would be spent on sending people to class. If you're going to pay for people to attend class why not increase your adoption fee by $50 and then give everyone $50 back for class. You won't lose money and people will think they're getting something for free!