Yeah it's not common slang. Though there was a character who used it in a line from the highest-grossing movie of all time. I think he was talking about money. He may have meant that the Pandorans were burying large amounts of cheese under their giant tree.
Always saw it spelt 'pedlar' myself. I thought I might be mistaken for a while but a comment here confirmed that is how I saw it written. No shrink for me this week... so far.
They're smart animals, they could respond to a variety of stimuli with training I am sure.