My first thought is without more information I would say this post is either B.S. or there is more to the story either purposely not being shared or mroe to the story than "pcosho" is aware of (i.e. the comment was intended for someone in their own group)
and worse case scenario, the comment WAS intended for "pcosho" and their group and NOTHING was done to deserve it, then the person was probably having an extremely rough day. no telling what had happened.
I have been working with the department of defense, military, mostly Marines and Navy, Air Force on occasion for over 20 years and I can assure you that most service member have and show more respect for people than the general public.
so if this did really happen and it wasn't warranted I assure you it was an isolated incident.
As others have mentioned however, if anyone notices a service member "ESPECIALLY" in uniform exhibiting actions unbecoming of a service member and you feel you need to report it get the persons name, rank and report it.