"In the absence of dancers, I see nothing inappropriate in percussion filling the sonic space that might otherwise be occupied by feet."

Well I just might. This is an interesting new concept in music, that tunes are provided with "sonic spaces" begging to be filled. Especially by some skin-bashing dolt. However, tunes ~are~ provided, gladly, for people to dance to. If they happen to clatter their feet whilst so doing they are (a) not consciously doing it as a contribution to the music and (b) doing it with the blessing of the musicians. So comparing what dancers do with what goat-whankers do (that was on purpose) is hardly valid.