Recently Mothers Against Drunk Driving (MADD) leveraged a #hashtag campaign. It put out there a petition to have the Affluenza miscreant treated as an adult by the law. The organization expected it would take them a while to collect enough signatures. That was done in a day.
During the holiday season Reese had a #hashtag campaign rescuing its treat shaped as an irregular tree from disaster. Some had saddled the candy design as a dead wringer for poop. The campaign was effective.
But, the #hashtag is no longer new. To work it has to have a compelling or clever reason to trot it out. MADD had the compelling one. Reese leveraged humor, that is a clever trick.
In PR Week, there is a debate if the #hashtag is dead. As the two examples above show, no, it isn't. But it could sideline a campaign if it is used just because it is there. This is analogous to why so many webinars fail to influence or sell. They are being used as platforms for messaging just because they are there. Yet, there is often no one there to view them and respond to the Call To Action (CTA).