I've always self funded charity rides, just my nature. If the minimum is too much for me to swallow, I don't do the ride. It's not for me to say how much is "right" and more than that is "greedy." Probably each event has staff that figures what they need from each rider to make it worth their time. I might disagree with their assessment but it's not my ride. Lots of stuff to get riled about, interesting to hear what does it for others.
