Public wifi & bandwidth throttling question

My local cafe’s wifi access point works great in general, but for some reason Facebook times out about 95% of the time. This seems to be happening regardless of whether or not other customers are also connected to or trying to connect to Facebook.

When asked, the staff don’t seem to have a clue about what might be causing it. Assuming the cafe isn’t throttling specific sites on their router, what else could be the problem? Is Facebook seeing that multiple connections are coming from a specific IP or range of IPs, and setting a throttle on their end? How would I determine whether or not this is the case?

While this is actually a very good thing for my productivity, I often spend the whole day here working on a project and it’d be nice to be able check in from time to time without having to use my phone.

Consider the case of universities, where it’s possible that an entire lecture hall has Facebook open on their system and you can rule out this possibility.

Well, yeah, you have a point there. I was thinking along the lines of the cafe router using some lame default setting for how it hands out IP’s or segments traffic or something along those lines.