re: US Marines confront 'fake sergeant major' at funeral

Non-military guy here and I have to say I'm confused by the negative reactions toward the marines here. What did they do that was so bad? They didn't raise their voices, they didn't use profane language, they didn't invade his personal space in a threatening manner. This dude was in a public area and I thought they were quite civil.

Now I've seen a few videos with the over-the-top agro-bro marine types that shout and grab at the impostor, verbally abuse the guy, curse, get violent, etc. Those other vids can be way out of line. That didn't happen here.

What's the problem? How were these guys out of line? I was expecting much worse hearing the reactions. I thought they were fair, relatively composed, and did nothing at all to "embarrass" the marine corps.