We have 4 turkeys on ice that I'm going to be cooking for other folks, but I'm doing it through my church.
I do it for selfish reasons though, it makes me feel really good.
The first time was about 4 years ago. We were up at 4 am cooking, and by the time it was all over and we got back home it was nearly 5 pm.
My daughter asked, "where's our turkey?"
Oops. Forgot about that. We went out to eat.
If you want to leave food anonymously make sure you leave some sort of note explaining it and giving some sort of hint as to where it came. No names necessary but they have to know at least a little.
Many of the people I've come in contact doing this sort of thing with are very proud and it's hard for them to accept help. If not handled correctly a simple gift of charity can hurt more than it helps.
Could you imagine taking food when you had absolutely no idea where it came from? I can almost see them wondering if every person they met was the one who gave them food. That would be very embarrasing.