Well, he did invest in bitcoin because of the current value of the crypto currency as well as the plan he has for his company, Tesla. He knew that Dogecoin was only new to the frame and has not gained momentum like the bitcoin. If he had not invested in Bitcoin, then it would not have even been dogecoin as it was far from other coins in terms of the value. Just maybe, he would do that in the future when dogecoin starts having value. Hence, I am not surprise at his decision. Remember, it is in bitcoin he plans to start accepting funds for the purchase of his Tesla Car.