I can best explain why with a experiance i had
i went to a big concert this summer known as DFP 4.0
hte ticket was
Stone Temple Pilots
for the first three bands the crowd was running rampid kids and everybody was moshing
then STP came out and pits started in the beginging but there live show was so great people wanted to watch, and for Ozzy its always a blessing from God to be able to see him, everyone was standing in awe for him, and i dont know about Creed because i left as did about 3/4 of the crowd at THe PNC arts center, That lead singer wanted to close over Ozzy Osbourne now thats just wrong
so in conclusion for great bands people like to watch them and see the greatness that they are (For sucky bands people dont go crazy either they usually just walk around or yell at the band)
"You look down at me and see a fool, you look up at me and see your lord, you look at me and see yourself"