Diplomacy for finding merchants who want your goods?

My players are doign some mercantile venturing. One is a venturer with +3 Charisma and also has Diplomacy.

Does diplomacy apply to the reaction rolls to see whether a merchant wants to buy the particular goods you're selling? The rulebook says you get +2 on all reaction rolls when you attempt to parley. Is this situation considered parley?

(I could see the logic in it going either way, but I'm certainly conscious that with basically +5 on the roll, the venturer will be able to get almost all merchants to buy his goods. Fair given his investment, I suppose...)