Odds does matter and they are particularly more useful when you want to see who is the favorite team. The favorite team or the team which is winning mostly gets lower odds and the weaker teams gets the higher odds. This is mainly true for the sports betting.
At first, I was confused by this.
I thought that the higher the odds mean the ones with the higher chance of winning while those with lower odds mean that they have a lower chance of winning. But that odds doesn't refer to that but it refers to the winnings the gambler could win. It does really matter to some since it is their first basis whether to bet on that team or player.