Because being pagan means to think, to question, to reason, to accept responsibility for one's actions, to understand cause and effect, to feel, to be independent, to strive to be the Embodiment of the Divine on Earth, and that there is no clear answer to sticky moral questions. That there can be light in the darkness, that not everything that lives IN the darkness is evil.
The Divine don't want unthinking obedience, like most religions claim...they want you to question, to seek, to find the Light and the Dark and the Balance. The Gods don't get upset when we ask them "Why?"...but too many faiths don't want that question asked because Man can't answer it.
Being Pagan means you look at the world through a different lens...in a different way. You can see the beauty in a twisted old tree, or feel the pain in a perfectly trimmed, chemically maintained garden. Things others consider shallow are seen as profound; and, things others consider profound are viewed as Shallow.
You say "Witch" like it's a bad thing!