You want to pick the 'favorites,' to get accuracy points. But you also want to pick some 'underdogs,' to set yourself apart from the pack. Somewhere in the middle is an optimal solution.
The NCAA men's basketball tournament is a huge money-maker, but you wouldn't know it from the coverage on TV.
Simply filling out a bracket – even with random or uninformed choices – is enough to boost your confidence in success, and to get you to put more money on the line.