[The Squatter of Amon Rûdh]

I doubt it. They have a hyphenated surname to emphasise the fact that they're not of Bilbo's immediate family. The name does convey a feeling of snobbish pretension, but it's not the slightly French flavour of "Sackville" that achieves this but the tacking of "Baggins" onto the end. This used to be done by Victorian social climbers who wanted to advertise a marital connection with a more socially elevated family. Double-barrelled names are inherently pretentious.