I consider it a bug that it's possible to steal those potions after you've given them away and received the XP for curing that person. He/she should drink the potion, so there shouldn't be a usable potion in his/her inventory. While it may be a clever idea to steal a potion back, it's just abusing a bug (or at least an oversight) imho, and that shouldn't be rewarded at all.
Being able to find a difficult way out of a dilemma now and then is fine, but this example just feels like cheating your way out of the dilemma.
