I'd blame the device scanning the bottle rather than the tsa in this case. One day something will explode because it was concealed in something unassuming because "what are they odds". I don't like it either but the solution is not to "train the tsa better" (even if that's an argument, it's not the argument in this case imo), if they get a positive readings for explosives and something happens can you imagine the ****storm that would drop on them? Obviously this was just milk but what can you do when something tells you otherwise. Like I said, tsa isn't given the luxury of using their own judgement.