EventReservation markups doesn't show in Gmail

I've tried to recreate the Flight and EventReservation examples with the AppScript Quickstart Tutorial. The Flight example (https://developers.google.com/schemas/reference/flight-reservation) is displayed in Gmail, works great, but the EventReservation example (https://developers.google.com/schemas/reference/event-reservation) is not displayed at all!

Flight markup was working with JSON-LD and Microdata format as well. I've tried EventReservation with all 5 examples on the page with Microdata format, no luck.

I've pasted the example in the Google Email Markup Tester tool and it was valid (as expected). Any idea what's wrong with the example event and how is it possible that Gmail doesn't accept Google's own example?

@BlackGhost EventReservation will not parse in Gmail, however, it does parse in Inbox. It will also generate a Now card and an entry in your calendar.

This is how the example from the documentation looks in Inbox: