this is entirely a 101 question, i think, along the lines of some others -- how does anarchy (the principle) work in real life?
the answer is... as best as we can figure it out.
my answer to the specific question is to have a policy with flex. for example, have a general rule (people can eat once they have been around for three months (or whatever) and have helped more than they've hindered) and then have back up plans for situations that don't fit the model that the rule was created for.
i work with a project that has historically been very ambivalent (not in language but in deeds) about whether it wants to be a social service agency (charity), or an anarchist resource (to the extent that those are different, of course). i tend to err hard on the side of the latter, but i actually think the ambivalence works pretty well to keep things fluid and flexible, even if it drives the regular participants crazy sometimes. i bring up that example to demonstrate that people's different goals and skill sets, even (especially?) when contradictory, can work together to create something stronger. this sounds like an after-school-special message, except that the contradiction part is what i'm trying to emphasize, since it's almost inevitable and not usually appreciated, and is the most interesting part.
edit: i wouldn't try to say you're avoiding property. property is a reality in this world. pretending that people are not operating in that context doesn't work. it just makes people feel/act crazy (like there some rhetoric that people have to talk in order to participate in the project).