Surely it's a reflex when anything is placed in your hand or on the table in front of you? Today I fed my Y7 Spanish class various Spanish bits and pieces. I had three of them pass out the food at a table while the rest came up in groups to be served. I gave out seconds myself to those who wanted them.
I didn't do it for the thanks, I did it for them to have the experience as many have never been to Spain and those that have have tended to eat pizza and chips while there. However, at the end of the session, it occurred to me that not once had I heard the words "Thank you" addressed to myself or the kids serving the food. Is this normal these days? Surely not?