Gitz --
Of all the times we've been to Disney, and using an Ultimate Park Hooper pass each time (the pass was linked to our Disney resort card/key), we've never had to show any identification.
Of course, that's not to say they never do, but I really doubt they would considering the inconvenience it would be to the user to prove he/she was the rightful owner (not everyone brings id to the Disney parks).
Just fyi....This topic has been heavily discussed on this site, for the purpose of it being 'ethical'. I say, well, ...let's just say I wish I had someone else's PHP.