Cultural differences and free lunches

It is often said that there is no such thing as a free lunch. In fact, even free lunch at school for poor students has its price - shame.
To be honest, I quite did not understand where is the problem. When I was at school where subsidized lunches (not free, unfortunately) were available, everybody was happy to have them. Some people did not go to the lunch because they prefer to keep the lunch money, not because it was a shame.
It is a bit different in the US - one has to qualify, which means that at the same cafeteria, there are people who have to pay and those who don't. And those who don't are embarrassed by their (parents') poverty and allegedly prefer to be hungry.
This puzzles me. I would expect the opposite effect - those who get free lunches would boast that they saved more money; that they qualified for an extra benefit; that they get FREE! food. That was the way it worked in a poor country like Czech Republic.
But what do I know, I studied there in 20th century. It's probably similar to the US nowadays.

Free Food

I always thought that my everyday quest after the ultimate source of free food was specific to my preferences, while in fact, it is specific to my status of a PhD. student. I feel much happier now, knowing I'm not nuts and/or alone. Moreover, there is some chance that one day, it will be over.