Here in sunny Florida we have a great Supermarket named Publix.
And Publix is pushing Green Bags. 
 
(These days everything is supposed to be green.  When I was pushing
Green Building in the 80’s I was weird—-Man, who needs that, we are
making big money doin’ what we’re doin.—forgetaboutit.)
 
Buy a green bag, carry your groceries home in it and bring it back next trip—-
you will help save the planet.  You won’t need plastic bags if you have green ones.
Oh by the way, they are made with re-cycled material.
 
Well, if I use the Green Bag system I will have no plastic bag to put the garbage in. 
So what do I put my wet garbage in so that I can throw it out without dripping all
over the apartment ?  The answer is —
 
I can buy plastic garbage bags from Publix ——-Hey, that’s a great idea, why
didn’t I think of that.
 
So Publix will sell me a few Green Bags to replace the plastic they give me for nothing,
and if I want to have something to throw out garbage in they will sell me a different style
plastic bag.   I should have taken up merchandising in College instead of Engineering. 
 
Please note:  The word sell is used a few times in this post.