If it mattered to me that much I'd take it apart and unsolder the antenna then re-assemble and deny all knowledge.
Unless I owned the equipment then I'd just cut them off.
I just unscrew the little aerial when I use a wired connection (we don't have the public wifi rebroadcast thingy yet)
Looking for exploit was fun - found provisioned administrator password to access any modem on the WAN - but yes, unscrewing antenna is the first idea which comes to mind.