There are, I think, valid considerations as to colour. The 'wrong' colour is known to affect the resale value, or the ease with which the car will sell when you come to move it on. Not so much of an issue on a PCP, obvs (though I suppose it may have been factored in to the montly costs), but otherwise, a consideration. Secondly, I'm not only 'using' a car when I'm driving it. It will spend a lot of time sat outside my house, or place of work. If it offends me, or disappoints me, that will mar those other occasions, even if only slightly. Finally, as has been mentioned, people make unconscious judgements. If I see a grey Porsche, I think 'nice car'. If I see an acid green Porsche, I may fleetingly think 'egotistical dickhead'. It'd be interesting to see whether there is any correlation between colour and the likelihood of a car getting keyed.