I'd rather not buy it twice.

I think that if you already own the album, you should be able to get the music videos for free.
You shouldn't have to buy the song again just because you like the video.
There should be a way to do it, either by including a code in the booklet, or by giving the music program the ability to find the song itself.
And yes, I do realize that the producers and whatnot who create the video would probably not go for this at all since it would essentially be giving away their work for free, unless the person didn't already own the song and just wanted to buy the video.
(And yes, I also realize that there will be those who don't buy the album and still get their hands on it and therefore get the video for free, but they were going to get that album for free anyway.)