It's high because buying champs for a competitive game is fundamentally flawed at it's core. How much this really matters is definitely up for debate, but in a vacuum you can't have a perfectly balanced game if everyone doesn't own the same stable of champs to pick from.
That being said it's used as a crutch by to many people. You aren't losing because of this. It's an excuse. You in a general you=average LoL player sense lose because you just didn't play well enough, had bad team play, bad team comp, afkers, feeders ECT... verses the roster issue.
I do find it semi disingenuous in actual tournament level play though. Most of those people play so much though they own all the champs anyways.
Bigger problem with releasing new 6300 up champs every other week is rarely are the new champs balanced well out the gate. They tend to be OP/UP or just off.
When was the last time the next balance patch came out after a new champ had hit and said champ wasn't part of the balance patch? That should tell you something right there. Plus it feels like the more champs they add the harder it seems for Riot to keep things balanced overall.
Btw not saying this is easy. I'd fricking hate to be on Riot's balance team. That would be a nightmare to the MAX!
That's a good point. I guess the disparity here is you CAN'T be immediately competitive at a high level because of the level thing. You have to level up to 30. The time it takes to do that yields a pretty high amount of IP. I also believe that from a completely new player's standpoint, that leveling process is imperative to gaining the understanding necessary to play the game at that high level. Now an old DOTA player or something might feel the leveling to be too restrictive and would prefer to jump into higher skill games immediately. And then the lack of champions would be very restrictive.
I see the point though. Riot isn't directly selling power, but it's pretty close to it between the champion pool and runes.