Senua, I dont disagree. However even in sixth form, some engineering types will have often found each other and will have relatively little to do socially with those taking arts and humanities A levels. And at University there can be real conflict between flatmates who have to be up for 9.00am labs and those who have 8 hours teaching a week including non compulsory lectures.
Imperial is accused of being geeky, but the counterargument is that it can really suit geeks. The chance to specialise early, exposure to world class academics, London, with a brilliant variety of public lectures, a fabulously bright and international cohort etc. Imperial is the perhaps most generous University for providing bursaries, so if money is an issue they are worth exploring. It is relatively affluent and has impressive sports facilities. And there is a certain amount of mixing. You could, say, apply to an intercollegiate hall, if you did not mind a daily treck to Bloomsbury. DS, at LSE belonged to an Imperial sports society with a school friend in his first year, whilst his friend used to go to the LSEs friday night disco, reputed to be the best student night in London.
Earning money is easier in London. An awful lot of London sixthformers seem to get tutoring from Imperial students. Working for events catering companies in the run up to Christmas etc. Plus you are on the spot for network and recruiting events.
Yes students will be scattered. But the advantage is that social life tends to be concentrated around the University. More so, probably, than at somewhere like Warwick where second and third years will be a bus ride away in Leamington.
It wont suit everyone, but an Imperial degree is a valuable commodity and so it is an option that should be explored rather than dismissed simply as 'too expensive' or 'no social life'.