I've determined that the ability of banks to create credit out of thin air ultimately provides the impetus for the banks to use any marketing technique at their disposal to increase lending due to negligible or zero real cost.
This is how the housing asset market inflated to unsustainable levels.
Mortgages were predominately financed by peoples' savings prior to 1980 and therefore housing prices could not grow much faster than the rate of the economy.
When banks entered the housing market with full force, house prices began escalating out of control as lending surged, boosting demand, which resulted in higher house prices and therefore a false safety net of "collateral" to inspire further lending of money created out of thin air.
This unsustainable system was further compounded since banks began selling (bad) loans off their balance sheets, freeing up "capital" to be magically created and re-directed to the burgeoning housing market at zero absolute cost should the bubble burst. Of course, this only pushed the housing bubble out further and further to levels absolutely obscene relative to the growth of the economy and peoples' purchasing power.
Long story short, the ability for banks to create money has been abused and we were forewarned by the constitution's creators as well as Keynes among other economists as to the dangers of allowing private institutions to create money.
Only the government should have the capability of creating money and only through a nationalized bank.
Guess which is the only state with a surplus and with a gdp that has not exploded since the credit crunch?
New Jersey -- The only state with a nationalized bank.
http://www.huffingtonpost.com/ellen-brown/but-governor-you-can-crea_b_207806.html
Great site with more info on banks and money:
http://www.webofdebt.com/articles/dollar-deception.php