I would never think about Meetup for sports/casual activities. All Meetups I attend are "professional" events in my field. Perhaps Meetup has an untapped market?
Most meetups I attend are of the hiking / watch sports variety.
Apparently Meetup.com started out with this usecase in mind but evolved into what it is now.
It just doesn't evoke this sort of usage anymore.
Was thinking the same thing. Maybe it's easier to browse through since it's very narrow/niche? Hopefully OP can shed some light.