My guess is that for a lot of Porsche Design products, these are an answer to the question "What else can I buy that has the Porsche logo on it since I can't buy the car?" So some competition consideration is taking place when they set prices.

Porsche Design products (clothes, home appliances) are present in many malls, at least where I live. The design is very goofy (more so than even of their cars), and prices are competitive with higher-quality brands. Seems like there's a market segment which would trade some quality off for a sports car brand.

I personally do support your viewpoint, it's very unclassy to have anything car-branded if you don't have that very car.