I sometimes think that the _core_ reason companies like this take advantage of people is because people don't usually care enough to do anything about it; in other words, to care enough to help _other_ people out. I envision that in the future there will some kind of easy to use "web of trust" that people will look up before deciding to do business w/ someone. Review sites like Yelp/Facebook are just the start of this concept but I think it could eventually turn into something more robust.