It’s very rare to express emotions in land-based casinos. In poker it will be fatal. In other games it’s not a disadvantage, but players still prefer to not lose control and draw attention to themselves.
Online gambling is completely different – you’re at home and no one in the casino can see you, so it doesn’t matter how you act or even what you wear. But keeping your emotions under control is important even in online casinos.
The house edge in online casinos is much lower than in land-based ones because the costs are lower. So in theory players should have higher wins and smaller losses. In reality online players lose bigger amounts more quickly. That comes from getting emotional and not being able to stop playing.
The player who just had a huge win online feels euphoric and decides with excitement that it’s a lucky day. Therefore they keep playing and end up losing the entire amount they just won, and sometimes even more. The player who just lost a large amount gets angry and desperate to get the money back, so the keep playing and lose even more.
If emotions were under control in both situations and the players made decisions rationally, the huge losses could be avoided. Expressing your emotions is okay, but acting on them and forgetting about your original betting plan and limits is dangerous.
It’s important to practice making rational decisions from the beginning. If you fail to do that, it’s a first step to problem gambling.