I think I might have mentioned this before a few years ago, or maybe I only mentioned it to someone in-game, but shouldn't the quarterstaves and spears in Gullykin be changed to shortstaves and shortspears? Unless the majority of halflings in Gullykin have the monkey grip feet or out-of-the-way Gullykin gets a lot of out-of-town business all the time, there's no reason a shop run by a halfling in a halfling village would carry weapons too big for halflings to use. There just wouldn't be a market.
View of Gullykin store below from my halfling character's perspective. Yes, he has simple and martial weapon proficiencies. It's a size thing.
P.S. Also, the top three weapons are not in the similar store in the Underdark, inside that Merchant Coster building near that dwarf who gives the quest to fetch weapons from the mine in south S'shamath. I don't know if that's intentional or not, thought I'd mention in case it was an oversight.