I went through immigration 6 hours after the midnight deadline recently. I got an overstay stamp and a guy in that section told me he was being forced to leave the Kingdom - I didn't get the story though, but he looked in shock.
And it's not only a problem if one is detained. The ineradicable overstay stamp in the passport is the thing I'm always worried about. If the OP's never coming back to Thailand it's irrelevant I suppose.