To four people (my group), a tin of overlooked beans can mean the difference between life and death, so it's worth a shot. Also, because it's probably been looted several times, less chance of dead being in the area (all killed by previous raiders, or led off by them in the retreat). 

But yeah before we start, we need to know what the date is, and what the weather's upto. Just in case someone says about how hard it is to trudge through snow whilst getting chased by zombies, meanwhile two anime teenagers are making out in a sun soaked high rise. Keep things a bit more ordered etc.