Fashionable cars
The main merit of fabulous life is a fame you have and with that fame the trust of people comes. People see a celebrity they adore and – here you go- they are ready to do anything he or she will tell them do. Such a perfect feature of celebrities is like a Klondike for all those producers of something and they use this feature greatly.
Celebrities are the best advertising material for those who produce different stuff they want to sell. What's the point in asking some guy to say that this car is the best car, if there is a man known all over the world and it is enough for him to drive this car and all the people all over the world will be crazy about this car and no other advertising material will be needed?
So, as a rule celebrities get the cars they drive just like that, like a promo for all the people. They don't even have to pay for those, all they have to do is drive those and everyone will be satisfied. Though, that is not it, they also buy cars they want, cars they like. As a rule those cars are usually rather old cars of great value and price.
It is common for celebrities to have a good number of fashionable cars in their garages (well, the garage you are thinking about now is something different from one they have). So, the car they have is an inevitable part of their lives and their image and it is also image of the brand of car they drive.