Some of them do, actually, they think it is going to 400 or 1,000. They have no clue. Just take a look at the income statement of Telsa and you will see they are not making money. The number of people who can afford this luxury car is limited and by the time they come out with cheaper electric car most of the other car companies will beat them to it. I think there is a chance Telsa could go bankrupt in a few years.
Elon has had billionaire friends to watch his back. Then you have Elon himself. Now there's many videos and comments from Tesla customers who love the car. Then you have some states banning the company. That furthers its publicity. Your fighting against a cultural wave if you short this stock. Finally, the cars do exists. They are beyond theory and speculation. The model S does perform as advertised.