Starcraft 2 requires an astounding amount of strategy, skill and experience to play. LoL does requires some knowledge about positioning and ambushing, but when it comes down to it you only have to control 1 unit and concern yourself with the positioning of 9 other units. Comparatively, SC2 makes LoL look like a game for children. And, if you go watch a LoL event, you will indeed find that mostly children appear to be playing. I have not watched a lot of LoL, but from what I have seen it appears to appeal to 8-12 year old "pro gamers."
Now, there are a lot of games which seem silly compared to Starcraft if you are just considering the skill required in the pro gaming scene. The reason which these other games do not bother me, is that they aren't constantly grouped in with or compared with SC2. They are a separate community for the most part, which is probably for the best. League of Legends should not be compared to Starcraft because it is a completely different kind of game.
My opinion is that it is extremely inferior to Starcraft, but that's just one OPINION. Please, stop treating these two games like they are in the same genre or appeal to the same kinds of competitive gamers, because they DO NOT.