When booking a trip to the great wall, there's normally other stuff included, the better one of these are the Ming Tombs.
There can be a lot of other stuff, like the Jade factory, Tea Factory, ecc. It's all hoax, ticking you into buy heavily overpriced stuff, but also stops that makes the trip cheaper, so as long as you do not buy anything, at these places, you will be ok. The Jade factory even have, the lunch restaurant, where the included lunch will be, food was pretty good there !