Originally Posted by Juntima

Thanks for the input, this gives me hope

I have never leave without checking-out in person, so this could be a dumb question (please bear with me), but what to do with the keycard? Can I check-in and not accept the keycard, or is there a keycard drop box I just drop it in right after checking-in? Or I am to leave the keycard at the front desk upon leaving and maybe tell them I am not coming back (would this be strange?)
I am a little worried about not checking-out in person, in case they charge me for over-stay. By the way, it would be Hilton Garden Inn I am thinking of booking the stays, and it will be prepaid stay with a credit card.

Thanks again for advise