I think assuming porn production is intrinsically 'dirty' in a way that, say, a cocktail party with 20 ppl wouldn't be is exactly the sort of prudishness you're claiming is irrelevant here.
Hell, a family with three kids and a gallon of ice cream seems more likely to create an obscene mess than all but the most avant garde of porn (though I don't have kids and have never made a porn, so this is speculation)