“ Is it possible that there’s a “bulletin board” website at that airport and the request was simply broadcast?”
There are, yes. But most of it is informal.
We’ve got all the planes running to Houston to Midland and back on rotation for NAPE this week and trying to fill every seat with whomever needs it and other companies are doing the same for us.
It generates a lot of goodwill and is excellent networking.
I’ve only flown private twice in like 20 years. Both times I got the sense that the company that owned the plane was “filling seats” on a flight that just happened to be heading in my direction — and so the invitation was extended. It’s a different experience, that’s for sure.