It's not the marketing, as in advertising, that bothers me so much, as that's easily avoidable. It's the transparent targeting of demographics evident in things like artistic direction and content that does.
Games that are as blatantly targeted toward adolescent males as the "Graphic Tees" section of a department store immediately lose my interest. Basically everything DC has put out in terms of comics, games, animation, and film in the last few years is a prime example.