Update: Folks, I previously messed this post up! This is an offer for a free family photo with the Easter Bunny and not a free pet photo! You might be able to bring your dog or cat to this photo shoot. I honestly don't know. Your best bet would be to call ahead and ask.
To get your free free photo with the Easter Bunny at Bass Pro Shop or Cabela's, you just need to register ahead of time.
Registration for the event begins on March 25 and you'll book a free photo shoot on April 1-9. Then show up at the selected time and get a free 4×6 photo.