There aren't many living wage jobs for those with only a high school education so they have to go to post-secondary. 

Many high school kids cannot even get summer jobs any more because of the TFW programs.  

Domestic students can't pay someone to falsify their marks in the same way that can happen in foreign jurisdictions (for the purpose of applying here to go to school). 

The post secondary programs that have the best job prospects have become difficult to get into for domestic students because the entry has been inflated by foreign students  so they end up in the other programs and are then criticized for it. 

Foreign students are allowed to work here so guess who gets all the jobs on campus and surrounding areas (because if they work here they can also proxy buy residential real estate), so domestic kids rack up debt. 

Then they compete with everyone else in a labour oversupplied economy, for a scarce and declining number of lower paid jobs.