At a very basic level, they could offer live streaming of all events --advertising free-- for a fee. I would gladly pay, say, US $100 for this service. Some might only be interested in a subset of events, which means that there's a possibility to create tiers and capture revenue at various levels.
Here in the US, as has been discussed in this and other threads, NBC has royally fucked up things beyond all recognition. I finally broke down and downloaded their app. It's shit. The ads are intrusive TV-style ads. What's worst, they have some sort of a bug somewhere that is causing videos to end prematurely.
As and example, I tried watching Archery, Judo and Taekwondo pre-recorded events (not live). One of them was supposed to be a five hour event. We watched about fifteen minutes and the stream stopped with a message that read something akin to "This video has ended". There was no way to watch it beyond that point. It literally stopped in the middle of the action.
The other moronic thing is the way the video ads are inserted. They seem to be using a simple timer to determine when to run a video ad. This means that they'll interrupt your viewing in the middle of a match --just as someone is throwing a kick-- to run a stupid ad. Unbelievable.
I am hoping that there's widespread dissatisfaction with this and that the next Olympics, World Cup, etc. see a massive change. I'd really like to see a true Internet company get the rights and do it right. The IOC could make far more than what NBC and others are paying for these events by having a single-point internationally-friendly Internet strategy rather than old-school per country/region licensing.
Finally, a note to NBC advertisers: I am NOT watching your ads. Stop paying NBC! We DVR the coverage and are masterfully skilled at fast-forwarding through your commercials. When I am watching gymnastics I could not care less about your movie or your insurance offering. So, stop supporting broadcasters, you are wasting your money in a monumental way.