Many years ago there was a time when I had to choose between bus fare to get to work and lunch. I was very thin then. :)
We had a client, an elderly man who was working past his retirement years. He would stop by once every couple of weeks, always around lunch time, and every single time, he would call first and ask if we wanted anything to eat. I would always reply "no, thank you." One day he walked in, came right up to me and handed me a Cuban sandwich. Surprised, I said "I can't pay you for this." He responded "I know, but you don't deny people food just because they can't pay."
I follow his example to this day.