Ok, so I've decided to start playing around with balloon twisting because it just seems like way to much fun. I'm normally a high end card guy who does gambling stuff and I'm not really looking to add this to my show. It just seems like fun. Also I like it when things go bang. I've ordered some balloons on amazon, I've got balooning tutorials in my web browser waiting and ready to twist.

Problem is I'm a left wing liberal nut job who is concerned about the environment, recycles, composts, and is generally a greenie. You can all roundly abuse me for being young, dumb, and concerned about global warming and sea turtles later.

What do you do with popped and discarded balloons other than just pitch them in the garbage? I like the ideas I saw about taking practice sculptures down to Ronald McDonald House, and other places to give away, but what about the inevitable popped debris? What's an environmentally responsible thing to do with them?

All balloon sculpted animals will eventually end up in the garbage. They will not last in a child's house but more than a day and the parents will discard then. So you are kinda adding to the garbage problem even if you do not personally throw them out yourself.
Though call.... I guess it depends on how comfortable you are with this very small amount of garbage.
Certainly you create some garbage already right?
I have seen some extremely conciseness people that throw out less than a hand full of garbage a year but that is such a rare person.

If you could find something to UP CYCLE the debris into to, but off hand I have no clue.
Best of Luck.

Latex balloons are bio-degradable.

Reins for the pony, little bubbles for eyes, leash for the dog if you don't want to blow up another balloon, put them in a dog=worms

Latex balloons are incredibly 'Green' or 'Environmentally Friendly'
...comparatively speaking

http://www.qualatex.com/pages/facts.php

Your other question was what to do with the scraps
They're brilliant

I frequently use these for raisin twists, and other ways of securing balloons together
A little puff into a scrap, secured at both ends can easily be utilised to enhance simple structures into something with a wow factor
Using scraps to tie wire frames together at a stall

I like Plinks suggestion of giving a dog worms

Kudos to you for wanting to be environmentally concerned with balloons. I respect that.
However, regardless of what you do with your own cast-offs, the far bigger picture is that you can't control what happens to a balloon once you give it out. It's new owner will end up disposing of it somewhere.
They do bio-degrade eventually. But after seeing a bird swoop down and make off with a burst balloon of mine once I do worry what harm they could cause wildlife.