I think that the reason for the deluge of University graduates is, as you say, for the purpose of statistics. The Govt relishes being able to boast that a high percentage of people in Britain have University degrees; what they don't consider, however, is whether these degrees are actually academically rigorous or worthwhile. A degree can be in more or less anything these days.
As a result, the value of degrees has plummeted considerably. This is not only bad for the workforce, as it will be difficult - or near impossible- to differentiate between those who have respectable degrees and those who have done mickey mouse courses. In addition to this, it means that those who go to University with the intention of becoming teachers are generally less educated that is to say the standard of teachers is lower, meaning the overall education of the population has been lowered.
I think a lot of people are herded towards University, certainly at my school we were never actually given the opportunity to express that we perhaps may not want to go to University. It was naturally assumed everyone's applying through UCAS etc. They also see it as a way to buy some time and hope that a career 'develops' for them during their time at University.
While I wouldn't say that all students are 'aimless/carefree people' I think your observation is not far off the mark. The student image has been cultivated in recent years, that of the binge-drinking, foul-mouthed, lazy, workaphobe. This is true. These are carefree, aimless people, so I'd agree to an extent that a lot of this sort has been [mis] directed towards University.
With regard to degree difficulty, I have heard that 40% is all that is required in the first year to stay on the course. This, in a lot of people's eyes, gives them a licence to go out every night and throw caution to the wind on the premise that they need minimal grades to stay on and haven't a thing to concern themselves with.
These are just my humble opinions...