I try hitting 0 for an operator but then I'm prompted to give a 4 digit extension for the party I want to reach.
Just going with Occam here, but I've seen a couple of callcentre call-routing systems and the potential for misconfiguration is fairly high.
Or, if you want a more rational reasoning: nowadays higher education is essential to gain access to knowledge worker jobs which are becoming the foundation of the post-industrial economy. Nations should want the best quality of students in those jobs, not just those who can afford the entry ticket. Therefore it makes sense from an economic perspective to amortize the cost of entry (higher education) across the entire taxpayer base and leave education as a purely merit-driven system where the best students get the most economically significant jobs.
You can also try http://gethuman.com/