"Should donors care that the ALS challenge was a little high on the cost-to-raise-a-dollar metric? Well, I look at it this way. People did it because it was fun and for a good cause, and two years later we can point to concrete and significant scientific results from the money raised. That's not only pretty good, it's pretty damned awesome."
Don't let the otherwise informative post persuade you, donors should always care about the overhead costs of the charities they support. Just because an activity is "fun" does not excuse it from excesses and wastefulness. If people truly want to make a difference they should expect efforts be applied to progress, not enrichment.