It's all about dollars. And secondly about being calm and well spoken. If they think your a loon (if your raise your voice etc) they will roll their eyes and talk about you on break.
I'd go in and drop the booklets seperately from complaining. So maybe do the booklets first (great idea!) and then I woud go in and ask to speak to the manager. Let him/her know how much you spend on your pets each month, and that you will not spend a cent in their store if they sell rabbits. And that you'd be happy to return and spend all that money if they stop. And mention that you will be sharing that information with like minded pet owners, who will also take their business elsewhere.
Then I would have anyone else you know drop in and do the same, or sign a letter for you to give to the manager. If they think they will lose and not gain profit-they will stop. Remember petsmart? Everyone made a stink and boycotted and they dropped selling neutered baby rabbits
