I personally can't see the meat blanket thing as a reality check. Look, Marco did get conceited...but he didn't ask for a reward or a promise of a knighthood. He didn't act like he expected a reward either. River offered that to him freely. In essence, River built him up and then kicked his legs from under him the second he came to take him up on his offer. It was really mean of River and I can't do anything but feel bad that Marco was tricked by someone he called a friend.