This is the kind of statement that makes me long for a faceless, impersonal ISP. As much as I'm impressed by a neighborhood banding together and coming up with a solution, the idea of a neighbor trying to "figure out" usage or "talk to" customers about it is horrifying.
Hopefully they have a mechanism in place to allow everyone to burst to available bandwidth, but to throttle people to a sustainable proportion otherwise. Such a mechanism seems both necessary and sufficient, and given the professional equipment they're using, it seems quite likely to be available.
When Comcast sends bandwidth usage nastygrams, people get up in arms about it; we talk about "network neutrality", and that ISPs should remain "dumb pipes".
While the ability to introspect traffic at all is a bug that needs fixing in client and server software, to combat surveillance, at least with an ISP I'm reasonably confident that only 1) a trusted subset of ISP staff and 2) the government (hopefully with a warrant) have access.
By contrast, would you want your neighborhood association looking at your ISP logs? Or anyone you know personally? And making it their business how much bandwidth you use and for what purpose?
(On a separate note, I wonder how much Netflix's and YouTube's CDN boxes cost, given that Netflix and YouTube tend to subsidize them.)