Can't speak for chaosmagnet, but for me, you would have to define what "unnecessary weight" is for the situation that you're imagining you might end up in. In some situations a rifle might be considered unnecessary (localized tornado), but in others (large scale riots and civil unrest) I'd certainly appreciate having access to that heavier rifle and several large, loaded mags. Other times, a lower power rifle but better-than-a-handgun carbine might be what you want (e.g. Keltec Sub2k (folding), M1 carbine)

Also, some might be comfortable with a 6-shot .380 in their pocket for their normal daily routine, but feel better with a larger and higher capacity full-size handgun (and spare mags) in their car bag. IMHO, that handgun in your bag in the car will be next to useless much of the time. Additionally, it should be secured to prevent unauthorized access. IMHO, one needs to be carried on you (impossible to do this legally in some jurisdictions though). That limits size and weight, but gives you options to defend while making a run to your car for escape. Or if it's really bad, to access your larger gun(s) that are secured/stored in your car.