What makes some people that go to food pantries and soup kitchen seem so greedy?

I've been out of work for 9 months. Fortunately, I only have myself to support. A friend told me about a food pantry/soup kitchen where free lunches are provided as well as bakery products and sometimes fresh fruits and vegetables. I went to see what the situation was. I was amazed at the quantity of bread and other baked goods that were donated by local stores and specialty shops. I had filled two plastic bags with bread and set them down to look at the produce. When I turned back to pick up the bags of bread, two people were rummaging through them. When I informed them that they were my bags, one said "I don't see your name on them." It just seemed so desperately greedy and grubbing for them to do that when there was still plenty of food still out on the tables for people to take. What kind of mindset is this? Why do you suppose they did this?