They are not a threat in their own right but they are used to identify a person (or company) as Jewish so that vile anti-semitic people can then harass them online with abusive messages and images.

I don't think that the original post had anything to do with being proud or ashamed to belong to a religion - more to raise awareness of this disgusting practice, and to protect people from abuse if the (((hug))) is misinterpreted.