Help yourself!

So we have this new co-worker / intern in our cube. He just started yesterday. Today I ate lunch at my desk and after I was done I was about to go to the kitchen to bring some water and such. And this guy asks me to take his coffee mug as well with me. I was truly shocked, especially since I have barely know him for like a day. It must have shown on my face for he added -- "oh, can you just leave it in the sink? I'll wash it later." I'm all for dignity of labor and all that but whatever happened to helping oneself?!