Preventing such excessive behavior is a matter of discipline and willpower.
In other words, the stadium experience can be very instructive and maturing. But stadiums need a disciplinary system to perform these functions. The banning of the fan group because of the members who step over lines, who tend to be violent, and use inappropriate language, can be perceived as punishment rather, and cause anger. Moreover, such a measure can also cause and unfair system in which fans who follow proper conduct are also banned from attending matches.