heaalthy recycling

My very thin six-foot-three-inch son has a secret stash of food. Unbeknownst to me -- even though I've been trying to get him to take more food for lunch -- he only has a sandwich and drink currently. I just found out from his girly friend that he eats that sandwich by first period, then scrounges everyone else's lunch for more food. When I asked him about it, mortified that my kid is scrounging, especially since I've been urging him to take more, he said it's no big deal, he's recycling!