Failing Economist's cruel but fair remarks could be seen to negate the reason for studying an MBA. However, the students themselves said that contacts were the biggest single reason for doing the MBA, and as more than 50% of students finance (at least in part) thier own MBA, I have to assume that it either was worthwhile in a career sense or cheaper than a year long party - some party!
Of course, this discussion does not address the type or quality of the contacts that the graduates were refering to. I suspect that many of the contacts that were beneficial to the graduates were not the kind of contacts they would make at a really enjoyable party - or at least not at the kind of party that I would enjoy!!