I'm not saying this didn't happen but that sometimes paranoia plays a role on these forums. He might have just been walking through, and if I was walking through and someone aggressively got between me and my path I'd take a wide berth too. Maybe he just looked her way instinctively, I look at people around me all the time walking and half the time it's not even on purpose.
I've never had an issue at an ATM or Gas Station, not saying you should be oblivious but I do think there is a certain level where it becomes paranoia. It's easy to see the YouTube video where this happens and think it's common when it absolutely isn't. I'll probably get ripped up and down for this take but I do think sometimes as gun owners we are on such high alert that we see threats that aren't real.
Again, not saying this guy OP is mentioning wasn't a potential threat, I wasn't there, maybe he was. Just saying that I'm sure 9/10 of these situations are false alarms or mistaken perceptions.