A music video film?

It is quite funny that we always say this music is from that film, but we never or at least not often say the film is famous because of its music. Even for musicals, such as Singing in the rain, Chicago, at most of time we rather to watch the film than listen to the soundtrack. I am always curious that how come no singer wants to use their music videos to make a film? Or, use three to five music videos to make a short one. Probably there is not market for that kind of production or companies would not receive enough revenue to cover the cost. But, undoubtedly, a theme song can make the film much better. I guess that is because music can touch audience more directly, and music can make audience to remember certain scene in their life. And for those theme songs, they normally would use slow melody and simple lyrics, so that, they would reinforce senses like sadness or romance. Also, film and music has cross-promote relationship, it is hard to tell which one can bring more benefits from the other. Anyway, I think record companies can use their music videos to make short films and put them on internet. In compare of film music, that definitely will cost less and probably more viewers would consume this type of music production.