Well, if you do train for free, then putting down some coin for the grading isn't bad.
The organization I trained under had 2 prices for tests, varying a bit from school to school, but color belts had one fee, BBs another. not high, but no difference between 1st to 3rd. Never got higher, 4th had to test at a national event, in front of all the big wigs...
But all through that you paid your membership.
But no uniform
no dinner
no KKW certificate
no free rides.
(also, most BBs ended up in the instructor program...no free rides there, either)