I agree, but it's not such a narrow demographic. 63,000 bought them in Q1. The mode similar luxury/premium car I can find is the BMW 3 series. BMW sold 8,225 of them in Q1.

So almost 8x as many people bought a model 3 for similar or higher prices than the BMW 3 series. In fact at various time periods Tesla was outselling the sum of all similar premium cars in the USA from BMW, MB, Audi, and Lexus.

So sure Tesla owners are a self selecting set, but there's apparently quite a few people that want the model 3.