Hi Paul,
Thanks for reaching out–what an interesting potential use case for Event Tickets Plus! 🙂 Tickets created with Event Tickets Plus can be attached to any post, page, or custom post type, not just events, so I see no reason why this type of usage wouldn’t be possible. Tickets do not include an expiration date by default, but as the date of purchase is visible on the ticket, you’ll be able to quickly determine whether a ticket is valid before scanning it.
I hope that helps! Thanks again, and let us know if you should have any other questions!