Honestly, you don't have to.
The benefit we provide with having an account, however, is pretty great! If you sign up for an account, you can get notifications of temporary attraction closures and upcoming itinerary events (such as FastPass+ windows or shows).
Disney uses something called a "Xid" as a unique identifier for your account for their "My Disney Experience" stuff.
Rather than ask for your Disney username and password, we can use your Disney Xid to access your itinerary (including FastPasses, meet-and-greets, entertainment, and restaurant reservations) to send you notifications of upcoming events.
This part is a little tricky, but we believe in you!
window.PEP.guestLocators.xid = '01234567-89AB-CDEF-0123-456789ABCDEF';
Please don't hesitate to contact us if you're having trouble with something, find a bug, or have some suggestions on new features.