Nothing Bounces Like Beach Ball: Ask Liverpool FC

Did Graham Poll blow the call? Yeah, sure. I suppose it could be also be argued that Darren Bent struck the ball flush, that it's path was not diverted by the beach ball and that Pepe Reina should have kept his eyes on the more important ball. But the question of far more importance is why would any fan, let alone one at his own team's end, bat a beach ball onto the pitch?