I expect that in many cases this is only true because the advertising market is competitive - you can’t advertise less, or you’ll lose market share to your competitors. But if everyone is prohibited from advertising cars, is the total market for cars really going to shrink? And if it does, is that actually a net negative for society?
Anyway, marketing is a useless overhead in our society for the most part. Especially in the case of medical products, where you go talk to a professional, a doctor, who can recommend the ones you actually need.
“To what end,” my goal is to at least pin it to something that might have useful side effects, R&D.