Many on facebook take advantage of simple concepts to push their own agenda. Taking Random pictures and assigning one's own meaning without regard to context....being obtuse to promote one's agenda.
That picture clearly showed a picture of a happy infant, but your facebookism turned this into an abortiondiscussion.
When someone does something on Facebook just to make a point, or have everyone else see it. Can be done by a status, or joining of a group. Usually not a direct comment or wall post.