Dave that's just not true.
I think you are crediting The Great British Unwashed with far more understanding of how concertinas, bagpipes, melodeons etc are supposed to be played than is reasonable.
This show was NOT designed for the experts we find here on Mudcat. I do in fact play (to some degree at least) nearly all the instruments on display, and I didn't notice any poor technique at all (though I bow to Eliza's greater abilities here), I was just enjoying the flow of show.
Most TV programmes contain a few bloopers which only the initiated will spot, and no-one is sent to the Tower as a result.