It doesn't work that way. Sure they have to decrease their risk of loss and can't have their position be completely at risk. There will always be some balance and the odds can be shifted. But they are NOT in the business of just collecting vig. You can even see from the guys who do it. “That’s a fallacy,” former William Hill and Caesars Sportsbook director Nick Bogdanovich said. “It never happens that way. The books always have decisions. That’s the bottom line. And some are bigger than others.”
“Ideally, if you could be in that position, it would be great. But it’s somewhat of a myth to be able to divide action equally on every game,” he said. “We’re going to have a vested interest in every game in every sport.” said Red Rock Resort sportsbook director Chuck Esposito.
Vegas actually takes a position in most of the games. They trust that the guys who set their lines are so good at their job that they are trusting them to actually gamble with their lines to win money. The quotes are from the below, but any interview you see with the the actual oddsmakers, they always scoff and laugh at the notion that they are just collecting vig and collecting even $.
There is a popular belief that sportsbooks take an equal amount of money on both sides of a game to guarantee a profit. Is it fact or fiction?
www.reviewjournal.com