Why so difficult to find the airport chair 3 d model?

A lot of people want to find the airport chair through a network of 3 d model, is the lack of resources, and even can not find, what is the reason? 1, not every manufacturer want to fully display their own product, if you really want to find a factory can be individually, even to the manufacturer to see the real best. 2, design cost is high, not every manufacturer is willing to do a 3 d model. 3, the network to steal phenomenon more obvious, hard to figure was stealing. 4, resource sharing is not bad, but still have some secret is better. If necessary, contact the manufacturer.