Yeah...an e21 with an ///M3 badge is quite gay. He might fool his girlfriend, but not anyone with half a brain cell.
I was out looking for a new project e30 the day before yesterday. I stopped to gas up and this toolbox pulls into the gas station in a yellow e36 sedan. Nicely done up, but when I walked back to pull out the pump nozzle I noticed the M3 badge on the deck lid. I looked at the mirrors (obviously the stock, non-M mirrors) and then the tail-pipe. It was a tiny little single outlet (318i). And besides...if you heard it pull up, you would have instantly known it wasn't the real deal.
I couldn't help laughing at the guy. As soon as I said "Nice M3" he turned bright red. He was a poser, and he knew he'd been caught. What's funnier was that his girlfriend couldn't figure out why I was laughing at him. Too many posers in the bay area.