When love animals is said, it is said in a manner that actually resembles intrigue, awe, appreciation, and the mysteriousness of the animal. If a serial killer said they loved humans because they piqued their interest, then it would be the same deal. Which I'm guessing is true of some serial killers actually.
Not that it is right, fair, or even moral, the idea of seeing a completely unpredictable animal in the wild, having an encounter with it, and accomplishing the goal of shooting it is exciting to some. Killing one animal does not pose a threat to the entire species. As stated In a previous comment, it is percieved that humans develop more complex relationships and emotions than say a buffalo. So although you can say that one isnt as important as the other, it can easily be percieved as such.