I doubt that's why they are allergic to it. Perhaps I'm projecting, but I suspect that developers have seen their fair share of products which succeed (for some measure of succeed, e.g. "raised a round" or "founders cashed out") with only marketing and a crap or, worse, vaporware product. It's a very common and easy fallacious inference to go from there to "all marketing is bad", especially in a field where there are a handful of success stories (e.g. craigslist) where the success was built with very little or no marketing, and "the product spoke for itself".