Death stare from men

I grabbed coffee at a shop I frequent regularly, where I know the barista, though we’ve never had more than surface-level conversations and have no conflicts or issues. Today, as I was leaving and it was just the two of us in the shop, he said, “Bye, (my name).” When I turned around to say goodbye, he gave me an intense/death stare and maintained eye contact as I turned back around to leave. I didn’t think much of it at the time, but it felt creepy.

The next day, I bumped into a neighbor. I’ve also only had surface-level interactions with him and no conflicts between us. He, too, gave me the same intense/death stare and maintained eye contact.

Ladies, do you think maintaining intense eye contact/death stare like this is a sign that someone could be dangerous? I’m not saying they will harm me, but it’s a red flag that they could be dangerous?

Example of the stare: https://www.reddit.com/r/jerma985/comments/t9laxj/the_kubrick_stare_is_one_of_stanley_kubricks_most/