The nature of the seller's trade post made it apparent that he was clearly looking for pomade princes. Trades as such often attract sellers of either that exact hat or the same hat with another effect to offer on their trades.

Cant find physical evidence of it happening, but its an assumption based on the nature of the trade :P

[Edit] TBH actually, this could have gone both ways. Now that I think of it, he's basicly "offering" his snaggle + keys on a miami prince by making that specific trade post. Guessing its not sure since he's specificly aiming for miami and got smoking instead. Eh, I guess this should be close enough anyway