Well, Canadian and American officials officiate Canada and US ice hockey games, so this isn’t some IOC rule. I happened to be looking at water polo and team handball the other day, and continental neutrality is definitely not maintained. As for basketball, US-France had a Brazilian, Canadian and Italian. I suppose that’s neutral because it all ends up being a wash. But several other games have one or two European referees on a game with only one European team. I think what it comes down to is men’s football is one of the only places at the Olympic team level where there is a very diverse representation of teams geographically. There are only four European teams, after all. In most of the other team sports, qualification is more imbalanced (akin to the World Cup) either because those sports treat the Olympics as a world championship or the sports are more niche and not played as widely on a global scale. So the short answer here is FIFA does it because it can. As for 2010 WC neutrality, FIFA had it as a formal policy for a period around then. Look at all the youth events before and after. It’s a prime reason why Geiger was the favorite for the 2011 WYC Final. Why they initiated it and followed it rigidly for a few tournaments and why they abandoned it are questions that I don’t have the answers to.