[The Saucepan Man]

The only time that we come across "Snaga" in LotR is in reference to the lesser Orcs (generally scouts and trackers) in the companies led by Shagrat and Ugluk (Mordor Orcs and Isengarders respectively).

But, on reflection, the Misty Mountain Goblins were probably thought of by the Uruk-Hai as Snaga (Snagas?). Snaga, meaning "Slave" was, according to Appendix F, a term used by larger breeds of Orc, especially the Uruk-Hai, to refer generally to lesser Goblins.