If the "right", consensus pick won/covered all the time, Vegas would go bankrupt. Truthfully, the favorite is where the public puts its money more often than not, but the odds makers are good enough that underdogs and favorites over time each cover about half the time. If there's a weekend where the favorites overwhelmingly cover, the books tend to get killed. But they make it up on the weekends where the underdogs disproportionately cover.