Some smart and engaged local newspapers and magazines actively support their display advertisers with a promise to share Facebook posts and re-tweet tweets.
What this means is you run an ad and beyond the ad itself, what you post on social media can reach a wider audience as they promote you.
In one situation recently a newsagent reached 500 people on their business Facebook page and the share by an engaged local publisher helped them reach another 6,000. That single share brought in excellent new traffic business.
Sometimes, the value of an ad spend comes not from the ad itself.