In the 80's there was this weird movement about labeling people. Think Bill Engvall's Here's Your Sign bit, but in real life practice. As a way to help identify people's strengths and weaknesses, individuals were encouraged to wear a sign that expressed things like, plays well with others, or shame them for less positive behaviors.
As kids we're taught to color INSIDE the lines and that being different or going rogue by willingly coloring outside the lines is bad. We're taught that running with scissors is bad and dangerous, so who would want to promote that they partake in these behaviors?
Okay, okay, so running with scissors may really be bad and dangerous, but it's still funny.
Sadly, though, these designs have run their course and we must move on, but don't worry, we've got plenty of other mildly inappropriate designs for you to choose from.