Speaking to Australia's News.com.au, the former Smiths frontman reinforced his anti-monarchist views by claiming the royals are "the most arrogant people on the planet".
"I wasn't surprised by Harry in Vegas because he's always been an absolute idiot," Morrissey said.
"The monarchy is foremost a business, and it's important to them that the British public continue to finance the excessive luxurious lifestyles of the now quite enormous, wasteful and useless 'royal' family. I find it very sad.
"William shoots deer, Kate's favourite food is the shockingly cruel foie gras, Harry shoots water buffalo."
He added: "They are the most dysfunctional, unpleasant and arrogant people on the planet. A sour soap opera, and they should resign and retire.
"Can you imagine how the Prime Minister of Argentina viewed Harry in Vegas? Or the Pope? Or the Archbishop of Canterbury?"
St James's Palace confirmed today that it will not pursue a complaint against The Sun for publishing the naked photos of Harry which trigged 3,600 complaints from readers.
Morrissey caused uproar back in August when he compared the effect of the London 2012 Olympics to Nazi Germany.
Watch the video for Morrissey's 'That's How People Grow Up' below: