There are talks of FIFA selling a share in the World Cup to outside investors for something like $20 billion. It sounds absurd, but I suppose it's not all different from FIA and FOM controlling different parts of F1.
Personally, I think it's a terrible idea, I don't see the upside (aside from rich people getting richer). FOM has done a great job of making money lately, but I do feel like there's too many times when FOM and FIA are at odds of what's best for the sport. One body makes sense to me.
In ice hockey there is the IIHF, and the NHL. IIHF events are rarely 'big money makers' (World Championships, Olympics), where NHL controlled international events are often exciting events with a lot of attention (Canada Cup, World Cup, Four Nations). (The NHL has no formal affiliation with the IIHF. Though they often cooperate because the IIHF will sanction events and the NHL has to release the top players to play. They do play by different rule sets, which collided hilariously in this year's winter Olympics with the rink built to the IIHF dimension in length, but the NHL dimension in width.)