This was the aforementioned Nevada City when I bought it on CL.
Why would someone do that? I think this is more egregious than the hipsters who buy classic road bikes and turn them into fixies.
I've actually been trying to figure out a way to buy bikes like this just to rebuild them and re-sell them without losing money. I know people even make money flipping used bikes, but I'm happy to let the garage sale combers do their work. I'm thinking more of projects like the one above where I find a neglected but not yet vintage bike with a nice frame and rebuild it (retro-mod?) with nice new components.
I've got about $650 of recent purchases in the Buenos Aires build, but that number is obviously kept down by the fact that I had the wheels, tires and crankset already. I think it comes out closer to $1200 if I include the original cost of all components when I bought them. To me, this bike is clearly worth that -- it would be a steal for a new bike with a Reynolds 853 frame and 105 components -- but I think I'd be lucky to resell it for $650 if I were so inclined.