Singer Irwin Sparkes claimed the Tennessee band's headline slot was disappointing because it didn't feel "special".
"I saw them at Glasto and they are good but they just don’t put on much of a show," he told the Daily Star.
"You want something personal because you know they do it every day - you want them to make it feel special for you."
Talking about his own group's performance on the Other Stage, Sparkes added: "We did some dances on stage at Glastonbury. We like to put on a bit of a show."