Our league is a Vegas trip league. We pay weekly dues and at the end of the session, is one tournament for a trip to Vegas. Only the winners get the trip, and 2nd place gets nothing. If you win the trip, you aren't eligible to play in the 2nd session tournament. However, at the end of each league session, the league operator pays out a small amount of money to each team based on team rankings at the end of the league session. If you win the tournament in the first session, your team can play in the 2nd session, but would only be eligible to win cash at the end of the league based on their team rankings and not eligible to play in the tournament for the trip.
Also, lots of league operators get airfare discounts and hotel discounts. I know ours goes through a travel agent, so he'd pay a lot less than what I'd pay if I was booking my own trip.