Caitlyn's Headshot Passive Procs On Jhin W? (not sure if this is a bug)

I was playing a game as Caitlyn against a Jhin and happened to be auto attacking one of his traps that was visible under my tower. In between hitting it I hit a creep which brought me to enough stacks where my next auto was going to be a headshot. I then shot the trap again and it consumed my headshot attack.

I just want to make it clear that I'm not entirely sure this is a bug or if it was intended to be like this, please don't tear me a new one for not being informed. :)

Edit: Title should say Jhin E.