The simplest way to do this via Delta.com (if you have at least 25k miles) is to select a frequent flier award itinerary online (but not book it). It will show up in "My Itineraries" as a trip that has been bought and confirmed. This could then be printed and handed to security as an e-ticket. I've not done this, but it seems like it would be pretty easy. This seems like a pretty big loophole!