It'd be up to the server admins to provide them, unless some kind of automatic downloading post-game was done.
Here's a comparison:
Client side demos are recorded on the client's machine, so they only record the data received from the server, i.e what the client 'sees'.
Server side demos are recorded from the server's perspective- since the server knows the position of all the clients, they can all be recorded without increasing bandwidth usage at all. If one were to download and play this demo, they'd be able to see all of the action as well.