It does not make a difference at all because you have to actually go to a gym to use that pass and do the raid battle so why you want it to drop from a pokestop? Then you will have a pass but no gym to fight at, and if you go to the gym once every somedays you can do the raid and spin the disc afterwards to get another pass.
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Why don't raid pass drop from the first pokestop
All in the question , gyms is far so I can at least swipe the stop one day and do two raids the next day , niantic really going after rural players , I really hope they change this small aspect at least
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I think everything you win from raids (TMs, rare candies, etc) should be rare drops from normal pokestops like evolution items are. So that being said, it would make sense if raid passes came from them as well. That would also help rural players who may not be able to do raids everyday and might not even have TMs by now.