Mostly true. For things like futures bets, they are trying to balance the actual probabilities of winning the event, with the reality that more people bet on certain teams, with the need for betters to place bets on long shots. There are more betters willing to lay money on the Yankees than the Twins, for example. In Vegas, they also have to factor the amount of betters who live in California, and are inclined to bet on California (particularly Southern California) teams. They set futures odds while considering all those factors, and try to arrive at a number that will both generate betting action, and provide cover for the possibility of a long shot winning. Enough bets on the Yankees at 3-2, Houston at 5-2, and the Angels at 7-1 covers the possibility of the Twins winning at 60-1, for example, and vice versa. They absolutely want people betting on the Twins, the Rays, the Pirates, etc, and will extend longer than actual odds if necessary to generate action. They don't want to end up in a situation where too much money is on the favorite, which of course means the book is exposed if the favorite wins. It's not as precise and linear as "Twins -110 over Detroit" or "Vikings -3.5pts vs Lions," where they absolutely want the same money bet on both teams, but there is still some thought placed on generating action and limiting exposure.