I don't hate the bands because they're sellouts, I hate them because it all begins to sound the same after a while. I used to like Green Day, and there was a time in my life when Dookie was one of my favorite albums, but when I listen to it now, it's just not the same. I've given their other albums a listen, and they just continually get worse in my eyes. If you don't want to jam pencils into your ears every time you hear that awful, overplayed "Boulevard of Broken Dreams" I commend you. So basically, I don't care if they sold out, they just plain suck.
So no, HondaRacer, Green Day does not own me.
As for Fallout Boy I've heard quite a few of their songs over at my friends place, and it doesn't sound too different from the rest of the genre to me.
Trust me, the majority (not all) of pop punk bands nowadays are just glorified boy-bands who can (barely) play instruments. Their songs and albums sell on catchiness, which isn't always bad, but doesn't work out too well for the long run. Most of the pop-punk bands like Fallout Boy will be forgotten in 10 years, they're nothing special.
And no, ITR, I'm not too "hardcore" for pop-punk, I used to be a fan of the genre, I used to be a fan of punk too, but I just realized how repetitive it all is. Real punk is dead.
To each his own though, I just wanted to clear a few things up.