This bug appears to have presented after the most recent Fallout 4 Unofficial Patch update.
As referenced, the NPCs within the Nuke-World Nuka-Town Market will Not initiate nor provide Dialogue Options, besides for Mackenzie Bridgeman who will provide standard merchant dialogue and her lore. She will not provide a dialogue option to start the Side-Quest "Open Season".
I have the ability to test Preston Garvey dialogue regarding the Quest "Open Season", for I haven't started the Concord Questline.
Though having researched this bug, It appears to have presented in the past, which people reported they couldn't receive the quest from Preston either.
If it helps I can record this bug in action.