[kak9]

No statement on whether this should be true or not.

But the reason it was started was because students didn't have the credit history to get loans at all--especially since the thought was they had no credit to lose so they would be incentivized to just default immediately after graduating.

Which is why student loans were made non-defaultable, to make a market for student loans possible.

[t0mbstone]

True, but I don't think there is anything stopping someone from using this technique later to cleanly default on their student loans later on in their life, once they have built up credit history.