The principle behind this is that upgrading your car with glittery and shiny items means that the chavs are more likely to steal the bits or the car.
If a lovely durg user takes your wheels, best case scenario is that he leaves it on bricks, so no damage.
Or he could just leqave the brake discs on the floor, causing more damage that the insurers have to deal with - most people don't nick the standard alloys as they're generally toss.
The moral of this story is - you can't polish a turd - stop modifying cars if you're over 17 and have a proper job