At the risk of sounding like an old hag, I think things are a lot different now than they were 'in my day'. I went to college (polytechnic, not uni, but did an academic degree) in the early 1980's and then you could just bum around for 3 years and come out at the other end not that much worse for wear (not that I did that of course!)
Today, I think there's so much more hanging on your degree... if I were to lumber myself with a £20K debt at the very same time that I'd need to be starting a pension plan/buying my first home, I'd want to make bloody sure that I worked hard and got the most from it.
I came out of college with a 2:1, having had a lot of fun and living three totally carefree and irresponsible years away from home, thinking I was the bees knees and the world was my oyster. Getting a job was a bit of a reality check. I don't think my degree helped me practically, I would definitiely have been able to take the same employment path I have done without a degree, but I wouldn't have missed those three years for the world. In fact, I wish I had been a bit more irresponsible because you sure as hell can't be when you're paying a mortgage and have two kids to support!
Part of me hopes my boys won't want to go to university. Firstly because I don't have a clue how we would afford to support them; secondly because I'd hate to see them start their adult life in so much debt (there's plenty of time for that later on); thirdly because I think today you can get just as much career enhancement by vocational courses and on-the-job training; and fourthly because I'm not sure it is so much fun these days for an 18 year old. I'd rather fund them to travel the world for three years.