Buttons can also be used as a form of identification. Schools, businesses, and family reunions all use buttons for this very purpose. Buttons can also be used to inform or attempt to influence the beliefs of others. Groups protesting an issue often use buttons for this purpose. Buttons can also be used as novelties or keepsakes.
People involved in multi-level marketing are good candidates for buttons.
Many years ago, before I ever making my first button, I was involved with a multi-level marketing group. One of the members of our group made buttons and before the start of each weekly meeting, this enterprising young lady set a bowl of her buttons at our sign-in table. These buttons provided our group with a great way to get noticed in public, and to have people ask about our product, based on the message that was on the button. Of course you need to match the button's statement to the group you hope to work with, but MLM groups offer great possibilities for those of us who make buttons. Over the years I've done this many times, and with good results.