As if Kanye West already didn't have enough people giving you flak following his onstage antics at Sunday night's Video Music Awards, well, allow us to toss a couple more names onto the pile: Green Day and the All-American Rejects, both of whom witnessed West's hijacking of Taylor Swift's acceptance speech. Both had about the same reaction immediately afterward — they were dumbfounded.

"I don't know ... it was just kind of a bizarre moment. Kanye's always unpredictable," Green Day frontman Billie Joe Armstrong told MTV News backstage. "But you can't be responsible for every dumb thing you say."

"Someone always does something crazy at the Video Music Awards," bassist Mike Dirnt added. "It's kind of a shame for a young gal and her moment, but at the end of the day, anything goes here."

The Rejects were a bit harsher with their criticism when we spoke to guitarist Nick Wheeler and frontman Tyson Ritter immediately following their performance with Wale and the VMA house band.

"That was just plain rude," Wheeler snorted.

"But there are a lot of rude people out there. People in general are rude. I think everyone has rude moments, and I think he's gonna be really apologetic," Ritter added. "I mean, Jesus, she's like 15! Who picks on 15-year-olds?!? I mean, God knows I have, but I always say I'm sorry, so I'm sure he's going to apologize." (Swift is actually 19, but we get his point.)

And, of course, West ultimately did just that, posting an ALL CAPS (so you know he meant it) mea culpa on his blog following the VMAs.

The 2009 MTV Video Music Awards might have wrapped, but the party is far from over. Stay tuned for behind-the-scenes updates, party reports and much more.