You've gotta keep in mind that v1.8 clients could not play all of the maps hosted by a v1.11 server without downloading the new map packs (balanced & open call).
Likewise v1.11 clients could not play all of the maps hosted by a v1.40.655 server (open call 2, dox, it, etc...)
The players who complain about client side maps are the same players who complain there aren't enough maps.
You don't have to upgrade your version to download the new maps. The server can and should advertise a download link that contains all of the files a client might get kicked for not having.
