The sastras prescribe that before setting for lunch , one should go to the entrance of the house and watch for any guest who might take the food one has to watch for the duration of milking a cow. Someone comes along If you're lucky. If you are unlucky, nobody turns out. Then with a heavy heart that no one has blessed you with his presence that day, you go and eat your food.
It's amazing to see what sort of attitude people have had those days.
An aditi is not one who gives you a call and says that, “I am coming for dinner today. Can I have the potato fries?”. On the other hand, there a long list of criteria to determine an aditi starting from one who has walked a long way and is tired. In short aditi is a person who is not known to the gruhasta and qualifies certain criteria.
To feed such a person his caste is NOT a criterion. If the aditi is a brahmin there will be aditi pujaa too. One may in accordance to one's household acaram choose the place of feeding like the pial but one should never refuse to feed the aditi. It follows that once there is no dearth of food and people need not worry about the next meal what sort of society will exist!