Why are 20% of 18-24 year olds on a unpaid internship if the economy is so good?

http://www.mirror.co.uk/news/uk-news/dont-just-call-young-people-4205233 Instead of blaming young people for being sloppy and unmotivated, we need to look at the system which pushes them through university only to leave them stranded, jobless at the end of it.