The question is really, do they only want Barcraft in Seoul to stop, or everywhere.
If it is everywhere, then perhaps it doesn't make a whole lot of sense from a business perspective, except from the reduction in apparent viewer numbers. After all, the only hard statistics they can present sponsors are viewer numbers.
On the other hand, if they are only trying to stop Seoul Barcrafts, then it makes a lot of sense, because they want those people on site instead, especially for finals. I think I have read that watching GSL inside Korea is free, so I don't think it is a revenue raising exercise.
They don't charge admission to the Makdong studio and space is limited. They don't make advertising from the spectators either.
But if they ban barcrafts, why not ban spectators at their events? Same logic.
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