[Endy]

Primarily advertising and positioning themselves as merit-worthy schools in a specific field. It also gives the schools a way to sell more materials. Plus, it's a way that professors under the harsh 'publish or perish' regime can constantly publish visible content and keep their name out there. Beyond that, most people who take a free MOOC actually want the certification it leads to - and they're more likely to enroll at a school they've already become familiar with.