There's already a contingency for this: give your friends and family plenty of notice to do their own prepping (even share the steps you're taking, though never divulge quantities of your preps to anyone). Once SHTF, anyone and everyone coming to your door who isn't an immediate neighbor gets treated as hostiles. Easier said than done, but you'd have to be an absolute fucking moron to give handouts to those who refused to help themselves when they were given plenty of runway to do so. Some of my best friends still haven't done anything besides buying a handgun-- they won't be allowed inside.