Of course they have zero control over the actual outcome. What they do have control over is prediction of outcome. A good capper can predict what, 60-65% correctly? A good capper has a fraction of the resources available to them that the odds makers have. They hire the best statisticians, psychologists, and field researchers money can buy. They have access to pro teams that we can only dream about. They have complex algorithms written by the brightest nerds in the world and have all the right information to populate the algorithms.
A good capper can predict game outcomes 60-65%. I'm willing to bet the oddsmakers can predict outcomes at a rate of 80%+. Once you can predict outcomes at a rate this high you can set lines to induce action on the other side of what your model predicts, and make a killing at it.
In a way Tone is absolutely right, but what he doesn't realize is he just sees through the ruse. It's not a trap to him because he wasn't fooled by the lines. But a large population of the gambling public isn't informed enough to see through it and fall prey to the "easy picks" that go wrong. What's fair line value to some is a trap to others.
I will take this bet. Go find one of your vegas linesmakers (I mean, game predictors) and we will make this bet.