Duck-onomics

So yesterday I was taking a walk in a lovely park with a lake, and there were Muscovy ducks swimming around the lake. I fed them some of my bread, which they really enjoyed. I started to think how food is like money to them, no matter how much they get, they always want even more than that. And that got me to thinking, if I could somehow speak their language, how could I explain trade and economics to them?
Ducks make primarily three things. Their bodies grow feathers, which they discard at a certain level of wear. There are two levels of feathers, the large outer feathers, and the fluffy inner down. Both are oiled to keep the duck waterproof. (Which helps them float on the surface of the water.) The other are eggs, which they use to make more ducks. I don't think they'd be inclined to trade their eggs. Their feathers, on the other hand, were littered around the park.
I'll be imagining the ducks to be speaking in LOLCAT speak, because they're not very smart compared to humans. (Big human-style brains are metabolically expensive. We humans are the nerds of the animal world.)
Lesson for the ducks #1: Feather Plus Wood Equals Arrow

"WHAT GOOD IS ARROW NO CAN EAT"
Patience, my Anatidae friend, we're getting to that. I just have to establish some things first.
Lesson for the ducks #2: Down Feathers Plus Textiles Equals Pillow

Probably a really good one too, all natural and all that. All the humans love down pillows.
"SO CAN EAT PILLOW?"
No, ducks. But we're getting to that.
Lesson #3: Goods like pillow and arrows can be traded for monies.

"WHAT ARE MONIES? CAN EATS?"
No, you can't eat money, but we're getting really close to that, I promise. Next lesson.
Lesson #4: Monies can be traded for anything, including bread.

"NOMS!! BUT WE NO HAVE MONIES, GIVE US NOMS ANYWAY."
No, ducks, you don't get stuff for free.
"BUT WANT!!!!"
I see, I think you'll like lesson five then.
Lesson #5: Since all goods are interchangeable, you can trade feathers you don't need anymore for bread from a human like me. He (or she) will do the remaining transactions without you.

"...."
"...."
"WE TRADE RIGHT NOW K?"
No, I didn't bring any more bread, but you might want to start saving your feathers.
"CAN TRADE ALL FETHURS ME REALLY HONGRY!!!"
No, you need some feathers to, you know, stay afloat, but when some fall out naturally...
"ME PULL THEM, THAT NATRUL, NOW GIVE BREAD."
Maybe I shouldn't trade with you ducks, lest you destroy yourselves.
"NO WAIT COME BACK ME WANT MORE BREAD!!!"
Eh...you're eating well enough as it is.
"WHO TOLD YOU, CREYFISH?!?! CREYFISH LIES!!"
I'm going now. I think I need to talk to someone less...impulsive.
"ME NOT IMPULSUV, ME DUCK. YOU SELL ME BREAD NOW."
I'll bring some tomorrow. No trading.
"AWW, BUT ALL US LIKE NOMS!"

So...imaginary trade with the ducks proves...disastrous....and is accordingly not performed. Ah well. The ideas are almost assuredly too complicated for them.