Being safe in your business is a sure way to mediocrity and perhaps even bankruptcy. The big deal about Johnny cupcakes is not because they are making millions selling t-shirts, it's because they turned reason upside down to create a following. And that means doing things that are unexpected and beyond logic (selling t-shirts in stores that look and smells like a bakery?) because they can.
They probably did not require a business case to put a Ninja turtle trading card along with the t-shirt.
Be different, be bold and make a big deal.