This is the major reason that I decided that another year of ACO membership at north of 100 euros was just not worth it any more. So, when my renewal came up last month, I didn't bother.
Instead, the money I've saved has been spent with a ticket agency to cover their face value mark up (they are, after all, a business).
At least this way, I get the tickets I want, without the major annual "the sites crashed, I can't log on, there's no tickets in the campsite I want" ACO on-line tickets sales trauma.
Sod em!