Just as you can restrict what calendars show up in your "Suggest an Event" and "Make a Reservation" templates, you can also restrict what Self-Book templates show up in individual calendars in your account. This can be a useful feature to help you keep track of what Self-Book templates you like to use for individual calendars, or if others have Edit Rights to your calendar this will make sure that they pick the right template when creating a Self-Book event.
If you don't have any restrictions on your templates, all of your templates will be listed for your events and in your calendar's "Customize" screen. See the image below:
If you don't want certain Self-Book templates to show up in your calendar follow the steps in the image below:
Once you've made your changes you can then go back to your calendar, open the event editor, and you'll see only the Self-Book templates that you turned on in the list. See the image below: