The more I read the thread, the more I learn (honestly, not sarcastically).
I want to try and follow the money. The primary argument against this being successful is that it is not profitable, since it is still limited by the pro rata rule. I think that's a superficial argument at best, and here is why, from the profit motive perspective of each party to the transaction:
1) the pilot: while they could find people to fly with them to share costs on their own, this makes it a lot easier, and thus introduces a motivation to publish their planned flights in case someone wants to join in. I never heard of Airpooler before this, but if I knew it was legal, I would post my flights there too, because I love taking people with me and it would be nice to offset some of the cost of flying doing something I love. Money-wise, I would end up with more money than I otherwise would, so it is profitable for me.
2) the passenger: I get to fly on a little plane which is neat, and I get to pay less than I would to a commercial carrier. There is only a segment of the population that would think this way, that is, the more adventurous, but it is a decent-sized segment. Moneywise, if I needed to get somewhere anyway, I would get to do something cool and pay less, meaning more money in my pocket.
2a) Passenger, deux: this may be my only way to get to my destination without driving a car. Or this may get me much closer to where I want to go, which I could not do with an airline. Or this may be the only way for me to get there on very short notice without paying through the nose to the airliners. Or... there are many common scenarios, as we all know.
3) Airpooler: a broker with no liability and a website. The profit motive here is pretty clear.
I do think that like Uber and Lyft, this has the potential to upset commercial aviation on short local flights.
Now comes the question: is it in the FAA's interest to try and limit this?
I don't know. I am a big supporter of disruptive business models, and thus of Uber and Lyft, and my heart is definitely on Airpoole's side. The safety issue needs to be addressed, but I don't think the accident rate would go up. The main challenge will come, of course, after the first fatal that was arranged via Airpooler, which is why I think they did not fully think their model through; they needed to arrange a form of a rider to be offered via the site (or maybe even made mandatory) that both pilot and passengers could pay for as part of doing the arrangement. I'm sure there is an insurance company out there that would have been interested.
The FAA could also be more transparent and limit these to, say, non-Bravo and may be non-Charlie airports. Then there would be no direct competition with the airlines, and it might be easier for them to accept.
The blanket ruling really does seem like somebody is stuck in a bureaucratic mindset and enjoying their power to issue rules a wee-bit too much. I hope Airpooler finds a way to alter their model a bit and appeal.