I'm not so sure these concealed-carry fantasies work so well in practice, but that's beside the point.
The point is that if civilisation breaks down, as a lone wolf you don't stand a change, even when you're armed. You'll have to sleep sometimes, you'll run out of ammo, you'll run out of food, you may get ill. There will always be a `local community to support', whether you like it or not.
If you're unlucky the local community is a tribe of bandits that kills or enslaves you.
If you're lucky the local community is a tribe of bandits that demands protection money/tax/tribute. The resemblance to a getto gang, a maffia group, ISIS, Hamas, or an other guerrilla group may be painfully obvious, but they will be making you an offer you cannot refuse.
If you're really, really lucky the local community is a group of people that want to maintain some semblance of civilisation. They may even leave you alone if you don't look like a threat, but don't expect freeloading on any on the benefits of this community. However, if you're wise you thank your lucky stars that you have such a wonderful local community to join, even if they need your support.