In sports betting looking at odds before betting on a team is not quite good because I have often withness something like this before. So ever since then I always feel like to pick the higher odd but not everytime, because even the bookmarkers don't really know the final outcome of every game. So sometimes is good to take risks with higher odd because instead using a lesser odd that would make you feel bad at the end of day.
No the bookmakers don't know the final outcome or otherwise it would probably not be called odds and they wouldn't exist in the first place.
But I believe that they are feeding their algorithms with specific details about teams and what some consequences mean, like injuries or other events that have an impact. But I wouldn't be surprised if they are scraping the Internet for comments and information that people provide and then adjust their odds such that they know the odds will eventually give the bookmaker a payback regardless of what individual bettors win on their platforms.