It's sarcasm. (viz. George Carlin, http://www.youtube.com/watch?v=eGOBm2J4tn0 at about 2:20 in; the whole thing is classic Carlin at his most abrasive.)
For such an astute student of language, with an eye toward practicality over formality, I don't know how he could see a difference between his complaint that the colloquial 'save the planet' implied rather than explicitly expressed a human point of reference and his many rants against unnecessarily precise techno-jargon. (see: PTSD, pre-boarding, etc)
The only useful value in highlighting that 'save the planet' implies 'so we can still live here', is to draw attention to how the knee-jerk response to such slogans and policy suggestions [1] is the height of arrogance/ignorance.
But rather than exposing the absurdity of that knee-jerk response, his little rant has served as ammunition for that response, shifting the expectation of evidence of lasting harm to an intellectual game of pointless abstraction. [2]
As such it started, and continues, to bother me.
So, again, if you find any legitimate comfort in the idea of the planet continuing on without us (As Carlin may well have) there's no good reason to stop at that level of abstraction.
And if you just want to complain about colloquial language, generally speaking, that pursuit winds up on the receiving end of the bulk of Carlin's analysis of language.
[1] In short: dismissing any potential for a legitimate concern about defending life as we know it by casting conservationist policies as the work of extremists or dismissing any potential for damage by humans by suggesting that we're powerless to truly harm nature.
[2] E.g. "We may turn America's breadbasket into a dust bowl - but after we all starve to death, things will grow again!" As if that matters to the conservationist or their opponent, being as they would both have starved to death.