So the books don't just make money making lines because they're not actually accurate at hedging their bets. They are not merely doing the math, they are making some arbitrary pre-set decisions in some areas. The books dont have accurate numbers all the time for bets and this is an example. The books dont want money moving out of their little fish ponds they built as home where they must dominate the pond and not let sharp players bet because they point out the flaws. The books betting is a sucker protected area they build with the expectations a set amount of deposits are kept and some free and clear. The books basically are conmen that dont let other conmen into the action on a large scale. The books count on the money bet being kept, the way they take the bets is to make profit by their plans in a predictable way. It would be nice for a book to make more money on the betting volume and allow people to stay winners. Being bet limiting really sucks.