The whole environmental or frugal is like the health vs beauty thing.
I don't actually compost for the environment, I do it cause I hate to take garbage out
(truthfully the cat eats the scraps....)
I have found that the more I try to cook from scratch the less garbage I make, which is a good thing IMO, and the less I pack prepackaged foods for trips the less garbage....so environmental is good for the wallet (heh and often good for health/beauty too)