So as often as I have dealt with this, it just dawned on me how serious of a security issue it could really be. Anytime I've lost or forgotten my keycard, I've always been asked to produce identification to receive a new one (a policy which is taught and abided by quite well, kudos for that). However, what I just realized is that all too often (in fact I can't think of a time I've ever been ID'ed on this) when I drop by the front desk to request a late checkout and have to have my card rekeyed, I'm issued to new key with no request for identification at all. In fact the conversation is pretty institutional and usually goes as such:

Me: "I'm in room XXXX and I'd like to see if I can get a X o'clock checkout for tomorrow."
Front Desk Clerk: "Sure do you happen to have your key on you?"
The rekey the card and off I go.

If Marriott Concierge is reading this, you might want to send a note along to Corporate regarding this...