I enjoy wrenching on bikes in the off season. Come spring I usually have some to sell. I always post of CL and sell the bikes from my home.
Thievery.... is not a profession. Most theft is opportunistic. The skills of planning a heist (even through CL)... is greater than the average crack head bike grabber can muster. Sure there are a lot of big city bike theft... simply because bikes are easy pickings and very low risk.
But why would anyone go through all the hassle of a CL crime (that is also higher crimes and greater risks).... when they can walk to Star Bucks... and just wait a few minutes for their next new bike to show up?