Why don't Grooms wear white?

It's a clear cut rule only the bride wears white (minus dress shirts for some reason), but the groom wears the same/similar black suit to every other man in the wedding?

I know there's a mentality in Western Wedding culture that it's "REALLY about the bride" and the groom is meant to stand there and look pretty, but I'm surprised this hasn't become more popular as the times have changed.