What does the travel agency mean by zero self-expense?

It is a shopping spot that is not written in the travel itinerary, because now the Tourism Law stipulates that if there is a shopping store, you must write it in order to see your travel itinerary and some unpaid projects, such as some sightseeing projects (but it is impossible for you to go out with a group without spending a little money now, because going out is not so bad after all, as long as you can play well. )