I assume some here have seen this article making its way around the news--about someone using a ticket from 1994 to gain admission to WDW. I'm not totally sure why it is news. And I'm not totally sure why anyone was surprised the ticket was still valid. I'd be really mad if my tickets without an expiration simply stopped working. For that matter, we have many unused no-expiration days remaining and I expect them to be valid until I use them up.
http://www.fox35orlando.com/news/local-news/143201532-story
http://www.fox35orlando.com/news/local-news/143201532-story