What do these people actually *do* to deserve the title of celebrity?
They pay a lot of money to gossip magazines to print articles about them? :-)
Really, I don't know. Apparently there are people who are interested in their lives for some reason. I guess it's just a matter of being rich and showing up on the right places. As long as those people keep going to parties where a lot of gossip 'journalists' are and as long as they keep doing things that shock or otherwise might be interesting to the Great Consuming Crowd of Dumb People, they print and sell it.
It's just a matter of cooperation between these "celebs" and gossip magazines.