The short version: because we'd rather be beholden to our audience than beholden to people trying to sell things to our audience. The reason we can turn down a lot of advertising that doesn't fit with our network, making for a more pleasant listening experience, is because we don't rely on advertising revenue. We rely on you. We ask you to become a contributing member if you can, so that you and others like you can continue to enjoy the shows that you love.