Tom,
Take it easy . It´s not really an apples-oranges comparison (the job in question is NOT feeding cartridges). It´s about the question if a magazine could be (ab)used as a bottle cap lifter at all. As a magazine is a single purpose precision instrument, it´s not really relevant which one is more resistant to that kind of abuse. As you correctly pointed out neither should be used for it anyway. That doesn´t keep inconsiderate people from doing it though. That´s especially true when they are thirsty and don´t see a suitable alternative.