We just returned home from the 4 day Disney Wonder and had wondered the same thing. The last night before you get off the ship, they give out envelopes for the head waiter, asst. waiter, the maitrede and the stateroom host. I called the main desk and was told that the counselors are salaried positions and they do not accept tips, but instead mention and special counselor in the cruise survey that you turn in as you leave the ship.
Hope that helps...please feel free to ask any other questions.
Dianne