tor --version should imply --quiet
$ src/or/tor --version
Sep 29 12:34:31.993 [notice] Tor v0.2.4.3-alpha-dev (git-b9c86948e4f4f0af) running on Linux with Libevent 2.0.19-stable and OpenSSL 1.0.1c.
Sep 29 12:34:31.994 [notice] Tor can't help you if you use it wrong! Learn how to be safe at https://www.torproject.org/download/download#warning
Sep 29 12:34:31.994 [notice] This version is not a stable Tor release. Expect more bugs than usual.
Tor version 0.2.4.3-alpha-dev (git-b9c86948e4f4f0af).
$ src/or/tor --version --quiet
Tor version 0.2.4.3-alpha-dev (git-b9c86948e4f4f0af).
Noticed from #6996 (closed).