Not necessarily..there are bound to be nights when the guys are especially tired & just need to rest rather than hang out with fans for hours..especially if they've been on the road for a while and/or don't have many days off on their tour schedule. Sure, this sucks for the fans, but look at it this way: you go up & kick ass onstage for 60-120 minutes, & tell me the next thing you're gonna want to do is go talk to crowds of people you don't know..hell no. You're gonna want to go flop down on the sofa in the tour bus, grab a soda/water/beer/whatever, & just relax. Thankfully, most of the musicians in our genre DO take time after shows to let the fans know they're appreciated (& I have been there to see SymX drag their worn out butts off the bus after a show to do just that), but I don't think that skipping that on one night means anything has gone to their heads..more likely they were just tired.
Of course, if they avoid the fans regularly, then that's another story.