Hi Moritz,
Thanks for reaching out!
That setting actually controls where the ticket form displays on theĀ events page, which comes from our free plugin The Events Calendar. You can add tickets to other post types (The Events Calendar is not required to use Event Tickets and Event Tickets Plus), but since that setting won’t have any effect on them, it is only displayed when The Events Calendar is active.
If you do decide to use The Events Calendar, we also have an (unofficial) extension that will allow you to use a shortcode to display the tickets section within your post content – please see this post for more information.
I hope that clears things up, and please let me know if you have any questions!
Thanks,
Jennifer