Pailhead "No Bunny" - What's the Deal with Easter anyways?

Song:
Pailhead - "No Bunny" (yes, that's Ian Macaye with Ministry)

Many figure Easter Sunday to be at worst harmless. Just a bunch of families in their white best dress, running around having fun right? At best, it's the celebration of the Resurrection of our Savior and Messiah, Jesus yes? Right?

Or wrong? Easter sure has lots of Pagan following. Why is that?
What does the Bible say?