Well, it's cheaper than OSCON US (and you save on the travel too!).

It seems to me that there are two completely different types of conference. On the one hand, you have the grass roots conferences like YAPC and FOSDEM where everything is really cheap and then on the other hand you have the professional conferences like OSCON where you have to pay a lot more. The OSCON style of conference is aimed more at the corporate market where people tend to think that information is worth what you pay for it :)

There's room for both type of conference in my opinion.