Odd interaction with player

New-ish to the game (tried it upon release, just returned to give it another go), last night I was hanging around the Flatwoods area doing some of the Responders quest there when another player showed up. They were Lvl100, I'm Lvl6, they were decked out in some cool looking power armour and I gave them a little wave hello.

Then they stared at my character, and hid behind the nearest wall, just peeking out watching me, unmoving. I could obviously see them.

I ignored them and went about my business but every time I moved around I'd hear the heavy CLUNK CLUNK of their armour, turn around and they'd be peeking out from behind some other nearby scenery.

I tried approaching and they'd move away to peek at a further distance, they followed me back to my camp like this, hopping from tree to rock to tree and when I got back they just crouched motionless behind a truck staring at me until I logged out a few mins later.

Are all players weird like this?