Julian Cope presents Head Heritage

I don't think it's a problem asking someone nicely if they wouldn't mind moving while you take a couple of shots. I've done that on occasion, and people have generally been obliging. Other times, I've waited patiently for people to move (not so patient on the inside, but hey), but most times I've just been extremely adept at Photoshop (handy hint - if people are moving around, and not just static, take multiple shots from the same angle, and you can then clone between shots to make one completely people-free shot).