Why? Because!
We also have shops all over the Internet in many print-on-demand (POD) sites selling a variety of designs on almost everything under the sun. The only thing most of us have in common is that we love our shows and design for a living.
We are a group of people who love our TV shows and movies soooooo much we actually make and sell designs about them on T-shirts, hats, and everything else from eye glass cases to shower curtains.