There was a thread talking about this car and who owned it before, you can see the custom fog light inserts which that mystery switch toggles on/off. Plus all the carbon fiber wrapped extras such as the door panels, lower console tray, the dash with the suede leather look.
For being a professional motorsports dealer / reseller they sure don't know how to market cars. Showing a battery in the red (scares people away), dirty fingerprints and dust marks on the interior shots, and not very pretty shots of the car didn't help at all.
My guess is that the combination of the poor marketing skills of the seller combined with the custom work scared people away. As these cars get older I'm sure more people will gravitate towards the car being close to stock both inside and out other than the shocks, brakes, rotors and upgrades like that.