Jeese AcidHell, can you stop missing the point and read for a second. The ban is nothing to do with the wheel nut comming off. The ban is because Renault knew the car was unsafe before it left the pit box, yet let it go, they knew that while going down the pitlane it was unsafe, yet let it go, they knew when it joined the track the wheel was unsafe but made no attempt to even tell the driver, and that they let Alonso carry on around the whole lap thinking it was a puncture.
If Renault had jumped on the radio when Alsonso was goign down the pits, or even at any point before the wheel came off, and just said "the wheel nut isnt on properly, be carefull, bring it back and we will fix it" they would have been fine. But the stewards have reviewed the radio communications and no such communication happened. They knowingly let a dangerous car onto the track, and concously made no effort to prevent it joining the track, or inform their driver of the danger. Its that lack of communication that got them the ban, not the fact the car broke.
The reason why we havent seen this before is because I doubt any team have ever been this stupid before.