It is quite possible that this can be misused and sastras cover that eventuality too. A person living in the same village can not be an aditi. If a person comes on a day and then again on the next day he is not an aditi. A person staying in a village but keeps visiting nearby villages and poses as an aditi is condemned by sastras. Similarly one who quotes his lineage and gotra and demand food is like a person who, eats what he vomited (vanthaasee)! He will be born as a cow in the gruhasthas household in the next janma!
What of those who refuse to do aditi puja?
When a gruhastha refuses someone, the visitor takes all the punya of the gruhastha when he leaves. Whatever sins the aditi had is transferred to the gruhastha who refused. For fifteen years the pitrus won't visit his house. Even if he does homas with 100 pots of ghee no benefit will ensue.
Such are the values that our forefathers had. Even if things have changed a lot and this has become difficult to follow one needs to contemplate on this wonderful concept.
Ok, so can we now sit down to eat?