£60 a week rent, no Council Tax.
£10 a week bills.
£25 a week on food.
5 or 6k after fees are paid is at the generous end of things - enough money for nights out etc. Remember they're only at uni for something like 36 weeks of the year.
And yes, the average SU committee member is a hooray with lots of dosh from bank of mum and dad.
Oh, and having been to uni and dropped out once, I can say that nothing motivates like a year doing dead end jobs beforehand.
And another thing. I knew of quite a few people who would accrue debt they couldn't pay off. Then they'd go to mum and dad upset because they couldn't pay it off. So the parents pay it. I'd hold some cash back for that sort of scenario.
You can always give them more if they're hungry, but you can't claw it back once they've spent it on champers and coke. And some students do.