granted, pete townsend had much better reason to smash his shit than the average bar band:
reason a) they only smashed stuff in the beginning to keep the audience from screaming for encores. no equipment=no encore. no one wants your band to play encores anyway.
I smashed a crappy homebuilt guitar through the speaker of a crappy homebuilt amp once. Afterwards, I noticed I'd missed the high voltage terminals by about 1/10". I stopped smashing guitars after that. Never started polishing them, though.