Piglins will accept gold blocks in bartering but won't give anything in return

When I was testing out the bartering mechanic with the piglins, I offered one a gold block, which it picked up, then to drop its crossbow and start attacking me with the gold block. I'm not sure this is intended as the snapshot news page said that only gold ingots could be used to barter, but it would make sense that they would also value gold blocks. So I'm just confused why they have such a strange reaction to blocks of gold in particular.