I've often wondered about this .... In home invasion instances, and other times a gun is used for defence (Not offense like LEOs storming a crack house or drug dealers, or Army Urban combat here), has there ever been a need to 'reload'? It is hard for me to image, that a gang of 4-20 guys would be be storming your house that would require so much fire-power. I hear of guys packing 17 rounds (now 7 in NY... probably soon to be 5 and then 1) as primary and others as backup, and having 'several' magazines ready to go.... Sounds like a war zone scenario to me. Of course maybe you 'need' that many with 9mm to do any damage
..... In the instance just above there was only one intruder.