Banditry in middle earth and the third age

[Zigûr]

Originally Posted by Rhun charioteer

But Saruman as Sharkey acquired dozens of ruffians to lord over the shire. Where did he get them?

Dunland, it would seem. Butterbur observes that "newcomers and gangrels [...] began coming up the Greenway last year". However, those among them who were "bad men, full o' thievery and mischief" were joined by Bill Ferny and Harry Goatleaf from Bree.

This suggests that the ruffians were a mixture of Dunlendings and Breelanders who joined them.

Originally Posted by Rhun charioteer

Was there a lot of human bandits scurrying about on the path the fellowship traveled?

We certainly don't see any during the Quest for Erebor or the Quest of the Ring, but perhaps they were driven into hiding by Tom, Bert and William in the former case and the terror of the Nazgûl in the latter.

Butterbur also says "we're not used to such troubles; and the Rangers have all gone away, folk tell me. I don't think we've rightly understood till now what they did for us." This suggests to me that the Rangers probably kept the level of mundane criminal activity in Eriador fairly low. As for Gondor and Rohan, I couldn't say.