If no one wants to advertise video games, no one's going to pay ZU to host ads for video games. If someone wants to pay to have an ad for a $100 ocarina on here, so be it.
It's the ads themselves, not the products being sold, that ZU gets the money for. By having that picture/link on the site, we're getting money. And quite honestly, I find it surprising the ads are zelda related at all.