Yes! I love this movie and Scott Pilgrim is an unrecognized classic.
And I appreciate that you pause watching R rated movies. I personally will watch R rated movies, I typically draw the line at horror movies for the very reasons you mention.
Sometimes I believe R and PG-13 are mostly marketing ploys. And this may have been one of them.
I know a lot of people feel the opposite way that I do: they think PG-13 movies are the problem.
Most studios will, after all, try to edit their R-films into PG-13s as a ploy to sell more tickets. And a lot of times that just doesn't work.
There are also a lot of glaring problems with the current motion picture rating system (The King's Speech comes to mind).
That said, I do find that the PG-13 version of a film is often better than the R-rated or unrated versions, because it leaves out the scenes that just don't gel together with the rest of the movie. And those ungellable scenes are often the ones with the risque content, for some reason.
I agree on some movies that R was more needed than a PG-13.