In Mountain Lion why do remote shells via ssh do NOT inherit the environment of the launchd parent process?
I've looked for an answer too and eventually found a related answer to this question, How to set system-wide environment variables on OS X Mavericks.

It is a security measure, particularly to ensure secure shell users with a disabled shell, where SHELL is set to /bin/false, cannot gain unsolicited access. 

One workaround is settting PermitUserEnvironment in your ssh config; please read security caveats in above mentioned answer before doing this.