I have always found the premise of “run for charity” or “jump for charity” weird. If I thought a cause was worthwhile, I would donate to it. Why does someone running or jumping have anything to do with me donating?
It seems like instead of having a hundred thousand micro-charities, it would be better if the money were just sent directly to a large charity that already operates at scale and can use the money more efficiently.
Sending $100 to Doctors Without Borders is far more effective than giving $100 to The Dr. Steffy McStethoscope Memorial Fund For People Who Want To Make Themselves Feel Good.
It's like "raising awareness." It doesn't help anyone but the people trying to make themselves feel better about themselves.
We could call it "taxes".
(assuming that the costs are not outright taken from the donations pool, then the reason is still money, but in a much more self-serving way bordering on fraud)