I feel like especially in sports betting this is very helpful. Its good to know who all the money is being bet on but also its a good way to see who the good underdogs to bet on are. If a high profile better posts that he's putting all his money on one team or one player and they are the underdog then that bet carries weight and is obviously calculated! Pay attention to this stuff and the results of them. When you feel confident enough use a professionals bets as a way to help you place your own bets
It should start with the fact that successful players will not share their bets with you, this will be done by those who aim to later sell their predictions for money. If players share their results, it is usually only the winning bets, while they prefer to keep quiet about their losses. This could work if there is a community of successful bettors who share their predictions and show their bets, but I think such groups are closed to the public.