Unless you are assuming that DEs found out where they were hiding prior to Halloween and therefore, they went under a Fidelius Charm, I think it'd be okay to have James simply go out for food. I read somewhere (not a fanfiction ;) ) that they lived since after the prophecy in Godric's Hollow as Muggles, you know blending in like all the other wizarding families there.
Would he still go into town and get food? Or would he wait until Dumbledor gave his cloak back? Could he put a Dissalusionment (I don't know how to spell that) Charm on himself to go get somwthing?