Well for a start you can't just buy Matte Paints like a solid, or metallic. You can buy a couple from the Aventador DLC and Matt Black from a Lexus LFA, but the others you cannot.
I'm not exactly sure why people love them so much though. I like a matte purple car with yellow wheels, or Matte Grey and Matte Pink wheels. However apart from this I don't find much use for them.
Standard cars although can be made to look less jagged and blocky if you paint them in matte colours.
Josh, that`s a question that has no real answer, like why do some ppl like Bugatti`s and others Red Bulls, and even some who like both, to each`s own.
I like Matte because of the way it looks at night under the lights.