Sending data multiple calculations?

[Sławomir Kmiecik]

I was reading this code today, and I found one thing that I don't reallly understand.

        if not invisible:
            for spectator in getSpectators(position, ignore=(self,)):
                stream = spectator.packet()
                stream.addTileCreature(position, stackpos, self, spectator.player)
                stream.magicEffect(position, 0x02)
                stream.send(spectator)

Is it necessary to parse data for each spectator? Data could be packet above loop, then just send it to spectators.