Poker Tour Workings

[RacersEdge]

I'm just starting to follow these high stakes poker tours, and I was curious how they worked. Do the name players get an incentive (free entry?) to play on these tours like the WPT? What's the incentive to make a pro not just stay in Vegas all year and just play there?

They seem to travel to a lot of out of the way places and I just wonderde what their motivation was. Obviuously money in some way.