I try not to complain about refs too much. We see the plays at a slowed down speed and perfect television angle. They have a split second from one vantage point with bodies flying all over. Reffing a game is not as easy as it seems from the couch. On top of that a very unscientific research tells me that many fans who complain about officiating have very little knowledge about what the rules actually are.
That said, today there were several calls that I wasn't completely sold on. And making it more difficult to know is that the broadcast did a completely horrible job showing replays of what happened.
One thing I can say is that 2nd and 3rd team players are usually more susceptible to commiting fouls due to lack of reps. As are players that are fatigued (like, you know, jetlag). So, some calls I may agree were not the best but the idea that tired backups made a lot of fouls isn't far fetched.