Would more people be nicer about the Middletons if the source of their money wasn't party bags?

They are entrepreneurs and successful ones at that. While they may be "commoners" they also behaved with complete decorum, the mother of the bride wore a very tasteful and elegant outfit and the Duchess of Cambridge can rightly be proud of her family. There is something incredibly hypocritical about a layer of society who did nothing to work for or earn their titles and inherited wealth but yet they still manage to sneer at others who dare to try and be financially successful. As to those who find the Middleton's business a source of amusement, I would opine that they pay taxes just like every other business owner.