You ask a good question, and I suspect the problem is that people believe that they have to have a "cool" animal such as wolf or raven if they are going to have a spirit animal. The truth of course is that the spirit animal comes to you because it has a lesson to teach. It chooses you rather than the other way around.
Personally, my spirit animal is a grey whale. In my coven we had some with cow, dragonfly, dog, deer, etc. Not a wolf or raven in the bunch.