I'm not familiar with AUS loan mechanics, however, "deferred interest" <> "interest free". There aren't federal 'interest free' education loans in the US that I'm aware of. All the federal programs I see have interest rates of >4%. Granted, it seems like that's a relatively low rate for borrowing money.

US federal un-subsidized college loans can accrue interest even if paying interest or principle is deferred. Not at all the same as interest-free.

Additionally, with some federal student loans, there are fees of 1 percent and up that are actually removed from the loan amount prior to disbursement that you're on the hook for repaying in entirety.

Also your $200k number isn't accurate; unless you're counting room & board which is different matter not directly tied to education. I don't disagree that the availability of funds seems to contribute to the cost of education, but that number is a bit high.

From teh google:

According to the College Board, the average cost of tuition and fees for the 2014–2015 school year was $31,231 at private colleges, $9,139 for state residents at public colleges, and $22,958 for out-of-state residents attending public universities.