I think it might have something to do with the fact that in Europe a lot of, if not most, of these sports teams and shyt started as small not-for-profit organizations owned by their members. Some of the biggest teams in the world are still just that like Real Madrid, Munich and Barcelona. At the same time you had very powerful and structured associations with FIFA and all the ones under them like CONCACAF, UEFA and their counterparts, where all these teams were members. Those organizations also run the national teams minus the olympics, so they have a whole system governing the whole world of soccer. That's also probably why soccer is a youth minor/G-league type tournament in the olympics. These type of systems and history also lends itself to other major sports like basketball and hockey.
Some major clubs tried to break out of the system with JP Morgan and do their own NBA styled league but the fans said they would boycott everything and FIFA/UEFA would sanction the fukk out of them.
NBA and NHL are pure business and have always been, and their power in relation to everyone else is on another level.