I don't think the marketing is entirely at fault, it is that a lot of consumers just don't care. People who are satisfied with average, low bitrate MP3 probably aren't going to get excited about higher resolution audio and video. "What the public doesn't know is what makes them the public."
Marketing is part of it, no matter if you agree or not, but you can't market a high resolution video system through commercials on TV or in previews on DVD!!!
In my experience the electronics retail giants don't know how to sell Blu-Ray either, only the smaller specialy electronic boutiques really try to sell it properly.
In the end, the Public are like sheep, they like to keep up with the Joneses, however the average Mr and Mrs. Jones are still on the fence about blu-ray because the price isn't there and DVD is still "good enough"!!!