Hoooboy. Lemme see... Kinks several times, Guess Who, Who, Muddy Waters, Screamin' Jay Hawkins, Bo Diddley, Donovan, McGuinn & Hillman, the Band, Clapton, Stiff Little Fingers, Violent Femmes, Ramones, Blue Oyster Cult, Alvin Lee, Eurhythmics, Duran Duran.... my memory fails me. Not all of these were exactly by choice.
Why aren't the Guess Who in the Rock and Roll Hall of Fame????
I actually walked out of a Marshall Tucker Band concert. Not because the performance was bad, but because the singer's voice was shot. It was awful.
I'll get flamed for this one... but... I had front row tickets for a Journey show once. (actually they were opening for Def Leppard but I hate, hate Def Leppard). Journey came out on stage and rocked. No props, they just came out and played what they were supposed to play and did it incredibly well. This was pre-glee, pre-newest singer, and pre-everyone becoming obsessed with Don't Stop Believin'.
ZZ Top has done the same thing the two times I've seen them. I've heard of other people having bad experiences with their shows, but my two were great.