The cost of people playing longer is relatively minimal in terms of actual cost with the low amount of power usage per game and equipment, the only real benefit I could see to speeding up play in tournaments would be to get them to buyin to another tournament more quickly. While this is speculation, I don't see a significant enough reason for them to try to speed up tournament play artificially. It may make their tournaments slightly more profitable but I imagine they get the bulk of their money from cash games rather than tournaments just like in live poker rooms as they collect money from each hand. They'd likely therefore be far more likely to rig live games than tournaments. While I doubt any legitimate sites would rig their games, it would make more sense to do so in situations where there'd be a higher profit such as cash games than tournaments.
