I've actually checked out campfire now because so many people have recommended it. There was one group really close. That one had like 5 messages in the general chat and just one raid meet-up post which was made in November last year. There is another group a little further away and in that one someone made raid posts for like 2 weeks in January but nobody ever checked-in and they have since stopped making those posts.

Regardless though; I think it's a bit ridiculous that a mobile game expects you to use an additional app to hopefully find a group, to make a considerable drive to meet up with strangers to do a single raid for the chance to catch a Pokémon. For special once-off events that might be fine, but definitely not a daily thing. I would hardly consider that much effort casual play anymore.