[ChrisZang]

Let me play Sherlock Holmes here:

So you drive to the Auto-X on street tires but change to racing tires there.
You untighten the nuts and jack up the car. Street wheels off, race wheels on.
Now you hand-tighten the nuts, lower the car, take your torque wrench and finish the job.

IF you would put the nuts on that loosely that they fall off after a few feet you would IMMEDIATELY notice it when lowering the car, as the whole wheel would tilt - right? And we are talking ALL FOUR WHEELS here. So your immediate reaction would be to jack up the car again, and hand-tighten the nut. The chances that this happens to you on all 4 wheels - impossible.

So IMHO there is NO WAY that the guy forgot to tighten the nuts, someone played a practical joke on him.

Now let's start the discussion how bad you have to behave at an Auto-X so that you motivate other folks to do that to you.....