This just goes for freerolls as money games are a bit more complicated. The average freeroller will chase for anything no matter how bad there odds are. The only way that I have come up with to beat them is value bet them instead of trying to make the odds unfavorable for them to chase. The main reason for this is these idiots hardly know what pot odds are so they don't know its wrong to chase.
My strategy also affords me the opportunity to make money off these people, maybe not as much as normally possible but I don't stand the risk of losing all my chips to a bad beat on the river. Now this is why my advice works: for one they chase even when its an all in bet, two they'll call anything,and three once they make there hand they take the lead in the pot thus letting you know you are beat. My stategy affords me the opportunity to make more money than I would otherwise lose to these fools.
Later in tournaments I do change my strategies and play more of a poker game than just the A,B,C game I must endure to build my stack in the early goings on.