Because of the first quote I would think long and hard before handing in my resignation (no matter how stupid I think the situation is). Some things like friendships are more important than expressing my personal indignations.
I once made a similar decision based on principle and I still regret it. Friends will likely still be there after the Pro and the current politics are long gone.
The main reason I don't take part in comps/leagues is because of all the seriousness! People moaning and accusations of cheating! It removes the fun!
I wouldn't leave a club because of it, I'd just carry on, play for fun, and leave all the cheating, bitching & whining to the serious people! It would seem the committees decision is wrong and final, accept that these are the type if people your dealing with, take it on the chin and enjoy the rest of your games!