Singing everywhere
One of the main things that happens in certain parts of the world when Christmas comes around, is the carolers that travel from door to door. Groups of people walk around and sing to everyone, sometimes for free and other times for money. But you should give them something for their performance.
They are not technically singing for free, it is customary to give them some money or treats that you have at home before you send them on their way. They do love singing and spreading the holiday joy, so keep the spirit alive and show them that you appreciate them for existing.