The Web uses HTTP as a transfer protocol, not a transport protocol.
HTTP includes application semantics and any application that conforms
to those semantics while using HTTP is also using it as a transfer
protocol. Those that don't are using it as a transport protocol,
which is just a waste of bytes.
This is a topic for some future IETF hallway conversation, not two
standards mailing list, so I apologize in advance for not continuing
this further.
....Roy