Brands want there product to be handed out to us so that we wear it in our 'urban environments' and promote them. I doubt you could bargain with them and say, 'please can you give us an extra £1000, so we can reduce the registration fee, and you can keep the merchandise that you have offered for our goody bags.'
But I agree with you. I don't think many people care about the goody bags or prizes. But they are there for a reason; it's part of the sponsorship deal.
yeh fair shout, ideally you would have both