Isn't part of the problem that Facebook limits the reach of accounts once they get to a certain size? My understanding is that they basically block you from broadcasting to your friends. The ROI of a small business is then limited because after a point you have to effectively pay for digital ads anyway.

Matthew Inman posted about this https://twitter.com/Oatmeal/status/923250055540219904

As an aside, this also reflects on the honesty of their ad campaign about supporting small business. If they really cared about small business they wouldn't make them pay to reach the audience they created on their platform.