I’ve been thinking about this for a while whenever I check the lines in different sportsbooks. We all see odds move up and down before a game, but the real question is, are those numbers actually showing the true probability of the outcome, or are they just being adjusted so the bookmaker balances the action on both sides?
For example, if a team is priced at 1.90, does that really mean they have a 52.6% chance of winning? Or is it more about the book trying to spread money evenly so they lock in a profit no matter the result?
It's very hard to answer, because if we go with your premises that the casinos are putting this to profit then it could be the case. However, it might swing a bit as let's say the game gets closer as there could be fans on either side trying to put money on the teams itself.
So it's really a combination of factors like what I mentioned, gamblers betting on either side, true probability base on math, or casinos adjusting it to squeeze profit in a particular game. Or there could be like news as the game nears that might change the odds for favorite to underdog or vice versa that the casinos can't control, - the market force.