Given the huge, living world that Larian has created wit BG3, I find it surprising, that the vendors/trading system is so non-immersive. Why would an arms trader (or any tradesperson) buy rotten eggs?
It appears one can sell anything to any vendor without upsetting them, which is neither realistic from the view of the world nor a common practice in D&D campaigns (at least not the ones I witnessed and my NPCs would throw the players out of the store if they came with such a rude offer).
I can understand, that it's tedious to visit a ton of different traders if the vendors buy only their specialization, and probably not what most players want, but if I offer 260 rotten eggs in exchange for a sword, I would at least expect a nasty comment and a change in disposition from the vendor.
Maybe add a toggle mode to turn on specialized vendors?