Nah, that's never a free. If the player isn't aware it's play on, then they can't be caught holding the ball (as long as it's a reasonable mistake, and they don't drag it back in or whatever.)
They never pay those.
I agree, but this one was barely 10m let alone 20m. My 3 month old daughter knew it was play on, so I'm sure the St Kilda player also knew.