We have a similar program here that we do participate in. Our school had to fight for a grant to get it, but they did. My understanding is that we have so many children in our school district who receive free and reduced lunches, they are concerned that these children won't receive addequate nutrition during the summer break. So that's why they offer free breakfast and lunch.
WE qualify for reduced lunches as well, so I certainly don't mind taking part in the "free summer lunch" program. Last year the school was nearly begging people to participate and come get the free lunches. If they didn't have enough interest we'd lose the grant for our area.
Adults eat for $2.60, so we do this a few times a week. (although that is a fairly expensive lunch for me!

I can eat much cheaper than that at home!)
~B