+1, although I'd go further and point out the vast majority of students get by on about £4,500/p.a. loans and don't top it up with a job.
They also don't pay council tax, which saves about £1,500 a year. Assuming you can rent a shared student flat for 30% less than a standard one, you've also saved another couple of thousand a year.
I bet they have similar disposable income to someone on a minimum wage job, living in a small studio flat.