Previously there were less TV stations (and internet streaming didn’t exist), so to try to drive people to the stadium, the TV contracts were written to prevent TV viewing of the game if you were “close enough to the stadium”.
and to make this more complex, many different teams have their own TV channels distribution contracts (baseball has lots of this).
The sports teams and leagues have not caught up with this simple fact: Blackouts do not drive people to the stadium. If people cannot watch the game on TV, there are about a million other entertainment options available, and if the teams want to add friction that prevents me from watching the game, I’ll watch something else.
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