Shornbeards was a pejorative term applied to a notorious clan of dwarven rogues who reputedly hailed from former Cardolan or Enedhwaith and had begun to infiltrate the Lone Lands in the years before the War of the Ring.
They did not really shave their beards (which would have been a great pain and dishonour, any dwarf would rather die or die from the feeling of disgrace alone) but wore their beards significantly shorter than the other known houses.They also were seemingly weaker and more diminuitive than common dwarves why some suspected them to be akin to the Petty-dwarves of old, perhaps descendants of the semi-legendary Ibunites of Eriador.
Most however simply believed them to be the descendants of Wicked Dwarves exiled from the Seven Tribes, much similar to the Dourhands.
Notes[]
The Shornbeards featured prominently in earlier versions of LOTRO and may have originally been intended as a stand-in for one of the seven houses whose names turbine/SSG is not allowed to use.However most of the missions including them and their backstory were removed from later versions of the game and all which remains is a small oddly named band of outlaws.