It isn't to meet people, it is just a tradition you drink alcohol at a friends house before going out because alcohol is seriously expensive and double that in a bar. So you might meet or already know someone there and get to the "I am attracted to you" place then spend quite a few hours with them at that house, then going out then going back to an afterparty, then you might have sex with them. Mostly if you already know them, if you don't making out is also an alternative.

Having sex with virtual strangers don't happen more often in Norway than anywhere else I would think, but you might have sex with someone and by having sex you are a couple. Because that is what the last weeks/months have been leading up to through various parties and so on.

I'm not explaining myself well I think.