Thats exactly it. In a typical gameweek I'll price up between 200-250 markets looking for a couple of prices I disagree with.
The bookie is not in the business of predicting the future, they are trying to balance the book so the odds available a lot of the time will not be representative of the actual likelihood of something happening.
Patience and discipline to bet a couple of singles each week is the way to make a profit at this game. Unfortunately people love to bet accumulators.