This bug concerns the level 40 class power of merchants- the ability to tame monsters by giving away items. For example, if a level 40+ merchant has a heap of 8 burb roots and wants to use one of them to try to tame a goblin, invoking the class power menu, pressing 'c,' and then selecting the burb roots will give away the entire stack without any warning. I believe that there should be a prompt asking the player how many they want to give away.