The most common complaint I hear is about events/facilities/catering costing too much.
I once got a snide email from a rider asking if the Midlander 300, costing £8 to enter, had a typo in the price.
You could do a RyanAir kind of pricing model:
what about the other Ryanair ideas?
* baggage fee; handlebar baggage free, thereafter £15 per kilo, after all the more baggage the longer the rider will take and use up that expensive hall hire
* speedy carding, for an extra £8 you will be allowed to pick up your card first enabling you to get into the fast bunch sooner
* credit card non-fee, anyone who sends in a postal entry pays a premium for shoe leather to the postbox / bank
* ride together, an extra £2 per person if you want your brevet cards together on the table rather than the default AUK alphabetical system
* £70 extra if you really insist on bringing a bicycle to the event
* £1 extra to have the infos on a scratch card with a prize for the most correct answers