It works because of the novelty and guilt factor. In general it wont work because people will tend to shave things in their favor. Tips have dropped from 15%

It works because of the novelty and guilt factor. In general it wont work because people will tend to shave things in their favor. Tips have dropped from 15% to 10%. If people paid what the service was worth, Wikipedia wouldn't have to beg for services. If it really were profit maximizing, Starbucks would be using. (I realize this is an anti-innovation cop out, but I think it's pretty much true.)