They are winning because they are skilled bowlers who companies want representing them.  Companies won't keep around staff members that aren't "cream of the crop" for long.

Do you think companies give contracts to anyone?  You need to have credentials to even be considered for being on staff.  Usually they end up using the equipment exclusively before trying to get on staff too so they can use that as well as part of their resume.

Staffers definitely have an unfair advantage...... and thats a good thing. They wouldnt be on staff other wise. As a staffer member, you're getting the benefit of having the newest equipment with no real guesswork as to how to drill it, what the balls do, and how they fit with your other equipment. Your objective as a staffer is to sell equipment. With that said, as mentioned before, you have to make everything they come out with look good, so there is always someone you can talk with and go to.