My neighbor has a hummingbird feeder, but they always seem to be in my yard. I'm not sure I've noticed any preference for certain kinds of lilies, but I would say they seem to spend more time feeding from my other types of flowers than they do on my lilies. (I grow almost exclusively species flowers that grow natively somewhere in the world.) Butterflies of all kinds (and other insects) are simply "fascinated" with my lilies. It is often difficult to shoe them away long enough to get a good photo.
Here is how a butterfly pollenates:
