Out of all the options, student loans are the only one YOU can control. I guess taking over responsibility for a loved one's finances could potentially be a "known" item.

The other options you present for the most part would be surprises, but a student loan is never a surprise. You consciously go forward, fill out the paperwork, take out the loan, and know you have to pay it back regardless of the job (or salary) you land.

That is really the point I am making. The other items are a bit of a surprise, student loans are a conscious decision.