Ok. So it's obvious that the similarities between Uber and Airbnb are the multi-billion dollar valuations and the regulatory red-tape issues. But it seems that the major difference isn't just that Uber is portrayed as Darth Vader to Airbnb's Skywalker today. It's that Uber came from seasoned entrepeneurs vs Airbnbs first-timers at the start. The same goes with Dropbox. Coming from an accelerator program surrounds you with dozens of people struggling and breeds more of a friendly culture. Perhaps it could be that there are "quasi" authority figures at the beginning in the form of partners who "accept" the companies into the program - whereas Uber had no such authority during its formation.
Of course, the sample size of 2 or 3 companies is just too small to draw definitive conclusions. Rap Genius had public issues and they came through the same program as Airbnb. Maybe Airbnb sees how much bad press Uber is getting and so is trying to do everything it can to seem friendly.