[TheCoelacanth]

Bookies have to eat. They are never going to give perfectly fair odds because then they don't make any money.

Also NB: The odds don't reflect the bookie's opinion of what the real outcome will be. They reflect the bookie's opinion of gamblers' willingness to bet on each option. The bookie is trying to get the odds-adjusted amount bet on each option to be as close to equal as they can manage. That way, no matter what the outcome is, they can just take the money paid by the losers give some of it to the winners and then keep what is leftover for themselves.