Re:QUIC and HTTP/3 Support Now in Firefox Nightly and Beta
by wildfire on Saturday April 17, 2021 @10:29AM
(#26844505)
Actually my typical coffee shop does not constrain UDP in any way; otherwise DNS would break.
They are not sophisticated, they just do not want people leeching large amounts of data via the connection (which they basically perceive as http/1 or http/2).
Anyone using "something else" is basically noise.
I would say they disable it deliberately to prevent VPN tunneling, its probably a sane decision to disable anything not needed for the intended purpose (or not putting effort in enabling it).