You're not understanding.
From 2005 to 2007, Fannie and Freddie bought approximately $1 trillion in sub-prime and Alt-A loans. This amounted to about 40 percent of their mortgage purchases during that period. Moreover, Freddie purchased an ever-increasing percentage of Alt-A and sub-prime loans for each year between 2004 and 2007.
It is a common practice among lenders to package bundles of mortgage loans and sell them to companies like Fannie Mae while still retaining the servicing of the loans.Fannie Mae purchases bundles of conforming loans from lenders. Conforming is a word used to describe loans that follow the Fannie Mae underwriting guidelines.
I understand it completely, trust me. I understand it much more than you. F&F were regulated in terms of what mortgages they could by. It wasn't until Wall Street, who had no standards whatsoever, were willing to buy every mortgage out there regardless of its underwriting. So in order to feed that greed, banks started lowering their lending standards basically shutting F&F out of that market. That is why F&F had to reduce it's underwriting requirements in order to compete with Wall Street. Because by law they were not allowed to purchase those type of loans. You can see it clearly in this graph how much the private sector took over right before the crisis.