In New York City, it was customary for the buyer to give a tip to the title closer at the real estate closing. The title closer is the representative from the title company. They are responsible for making sure that the mortgage and deed are properly recorded. The tip was to cover payment to the title closer for their services as they were sometimes not paid by the title company or were paid a very nominal fee. The New York State Department of Financial Services has issued regulations now stopping this practice.
You can read the decision here: