Why are there andean pipe music bands everywhere? all over the states, europe and asia. same sounds and cds?

you know the band of possible peruvians (and or central americans or other latin americans) that play annoying muzak-ish pan-flute music outside your subway station? well that same band, essentially, is playing in seoul, bangkok, tokyo, nyc, houston, boston, paris, london...only a matter of time before the mars rover bumps into one. and i want to know why? why has this particular slice of world culture (dubious designation in this case) been franchised so successfully? the players often look like victims of a modern sonic slave trade, forced to emigrate to a remote locale and play that drivel for hours on end everyday.