Apparently Caleb Followhill from the band complained a bunch about feeling sick and saying that his voice was shot. At some point, he announced that he was going backstage to vomit and that he'd be back later -- which didn't happen. The rest of the band apologized (profusely) and later hinted at "bigger" problems with the band. Lots of folks in the audience were upset about all of this. Either way, a bunch of videos sprung up on YouTube. But as quickly as they go up, Vector Management appears to be pulling them down. Now it's possible that some of the videos include clips of copyrighted songs, but the whole thing certainly seems pretty questionable, and looks like an attempt to stifle the video of what happened. Assuming that most of the videos only included a bit of music, but focused on Caleb's statements, it seems like there would also be strong fair use claims.
Now, I did just find the following video, which does not appear to include any music, but merely clips out the statements made by Caleb and then other members of the band. It's still up as I'm posting this. If it remains up, then perhaps the takedowns are only directed at clips with actual music in them. Even so, the whole thing feels sketchy and, of course, is only drawing more attention to the whole story.