I'm not worried about personal information, but if there is no connection from the door reader to a central computer, how would they print out the history of who's keys were used? Plug a computer/printer directly into the door? It also seems that a predetermined sequence of codes could be subjet to theft - especially to the programmers who created the computer - kind of like the ones who programmed slot machines to pay out if the correct sequence of "inputs" occured.

I also had an issue several years ago where I could not get back in my room late one night. Went to the front desk and they gave me a new keycard. Once I got back to my room I had a voice message from the front desk that my company credit card had been declined and could I please come to the desk to resolve it. I always assumed they intentionally disabled my key so I would have to go to the desk, but the night clerk did not realize it. Would they have done this?