What does everyone do with
 

the old parts they replace? It seems some could be rebuilt. I used to provide my old starter to the store so I could get the parts for less cost.
What should I do with the old water pump and thermostat, etc. as they are replaced?

Due to the high cost of labor and the low cost of modern automated manufacturing, often it is cheaper to build something new than refurbish old worn out parts. This mostly results in the old parts being thrown out. Rather than ending up in a landfill, hopefully your refuse processor recycles most of the materials.

Vertex auto is still offering rebuilt water pumps they may offer you something for you carcass.

^ very true

The Chinese GOV gives tax break to manufacturers using recycled raw materials where "additional" tax are imposed to those who don't. Surely they must have copied this model from other developed countries but still today I haven't heard of anyone else doing the same :/

It's improving every year here. In fact it goes too fast! scary

Each districts has recycle pickup services here now. You just need to call and they pickup your stuff at the door - e.g. they throw back $5 at you for your damaged starter motor, your mobile, your flat screen tv, your car engine, WHATEVER!

Your local metal recycler will take this stuff and give your cash. I had an old wrought iron and wood bench were the wood rotted out. Brought the iron to the recycler, got some money, felt good about so tuning being reused and I got to weigh my vcar on their scale. Not bad.

BTW - while there I saw a stack of old water pumps, starter motors, carbs, etc.