All player PED input into the system is taxed, or better said, output is taxed. All input (ammo, decay repairs, auction fees, estate fees, TT feeding, crafting resources) goes into the "magical loot pool", and comes out at a smaller percent as loot, minerals, crafted items. The missing percent is kept for the system maintenance.
Think of it as a LA tax. You hunt, get loot, or mine and get minerals and you do not see the tax, but the owner does.
Also, considering market prices and the general skill of the players, alot of resources are wasted by selling to the TT, missing shots, armor decay, weapon decay, missing hits, overkill, loosing half beaten mobs, dying while killing mobs, fapping, mob health restoring and others.
IF the "missing due to bad skills and gameplay" / "MA tax on input" is higher than 1, YOU can actually play almost perfect and obtain more resources out of the system as others do. Being said so, please comment on any addition to this document, I understand some economical workings, I am a programmer and this is more than logic to me.
You might also consider that skill value is small from the system tt value, wich means that the prices that are out there actually stand as a mid-point between what the system values skills and what they might cost you to get them. Some skills need about 800-1000 PED to reach the same ammount as found on a skill chip.