I agree, you shouldn't rely on others to make your own decisions. It's your choice how you spend a bit of your money for your own enjoyment. No one should be a voice of reason for your decision-making besides yourself.
I agree with you that there is no reason to rely on other's predictions either on sportsbooks or on casinos. There is no reason to rely upon casinos but for sportsbook, we may take help information on Google, FIFA website countries website for the team for cricket, and ICC's website and countries website for Cricket, and the same for others. Also, we may research on Google.
Decisions must be taken based on our own desires, because if we only follow other people in making decisions, then we will feel regret twice. It is not wrong to see and hear what other people predict, but in the end we also have to make our own analysis and predictions and compare so that we can make decisions based on ourselves, not because we are influenced by others. Actually, this can not only happen in gambling, but in real life we must also have the principle that every decision must be taken because of ourselves. If we depend on what other people say, then we will never progress. However, if we base it on our own choices, when something goes wrong that makes us make the wrong decision, it will be a valuable lesson for us in the future, which we will not get if we follow other people.