But it's very unlikely that those gamers will watch it more than one time. If they don't pick up the game after watching a tournament, it's very unrealistic to expect they will be there next time.
After all, what makes a game grow it's its player base. For a LoL stream to reach 100k viewers it's because they have a player base at least that big. You can't expect 100% of the people who know nothing about the game to watch the whole thing.
Those "10%" were watching IEM, that's why it reached 75k (?) and they were never seen again.
With all this what I mean is that those 10% can be anywhere. Fact is, the clock is ticking, once the new generation of gaming arrives, games that try to pull out the realistic card, such as CS:GO, will have a hard time to get those gamers attention. Unless there's a massive overhaul on the way (Something more than just go F2P), you can't expect an exponential growth.