ok, so i've got a question that's been bugging me for years! I've never gotten around to asking it though.. How do bands change channels onstage? Take Metallica for example, those guys never seem to hit a pedal.. Or do they and have I just been missing it? It really looks like they don't though. Roadies?! I know its probably such a simple answer, but i'm dying to know, and put my inner debate to rest!
They could hit a switch with their foot and you could just think they're tapping their foot in time.

However, the band has earned quite a lot of money over the years (oh really?), so they could easily pay people to deal with their equipment.
they probably have a guy that runs their pedals and footswitches.
my gear: ibanez destroyer( with gibson 500t pickup), epiphone les paul plus,ampeg electric, marshall jcm2000 triple super lead half stack
I've been watching video after video! I really don't think they're hitting footswitches. There are times (on S&M) where they're changing channels in positions that they couldn't have footswitches in.
Alot of famous bands have people who switch their amp channels and effect pedals offstage. Altho guitarists with huge pedal boards, like Froosch and Mike Eizinger of Incubus (watch the "Dig" video with the dancer on Youtube. It looks massive) do the switching themselves onstage.