People interpret "sharing" differently. Someone might share an article because he thinks it would be interesting if true, and wants to see more discussion of it

People interpret "sharing" differently. Someone might share an article because he thinks it would be interesting if true, and wants to see more discussion of it, and someone else might interpret this as vouching for the truth of the article. Even the same person might share something without thinking about it much, then get defensive when he's attacked for it.