A marriage without love is not a marriage. I can see why wealthy/Royal families do it to try and keep their wealth in the family, or to keep the bloodline "clean," but I still don't agree with it.
A good example of the changing times is how Kate Middleton, a common girl, married into a Royal family and has been accepted and embraced as a Princess. I doubt that would have happened many years ago, and even if it did it would have caused ridiculous amounts of contraversy.