The conditioner thing was definitely his fault. Pointing that sort of thing out runs the risk of saying you're paying too much attention to little details about them that most people wouldn't even notice. This is already in the territory of creepy if they're not also that conscious of you. The phrasing of it all did not help in the slightest either. Even if he thought they were in a position where bringing that up was within reason, and maybe they even are friendly enough in general for some comment about that, the way he said it all was pretty terrible.