The only time I take food for the crew is if I am flying late Christmas Day. Then I take an Oreo cookies and cream fudge my wife makes every year. But I make sure I know the crew and am reasonably sure I don't have to eat all of it.

I won't eat food offered to me by passengers. As several others said earlier in this thread, we are a target. Eating food from someone I don't know just doesn't make sense.

To answer the earlier question, there's nothing I've seen in my current FOM or in any other FOM I've used during my career.