* They may be feeling insecure. Being in a school band can be a lot of pressure. Students are expected to perform at a high level, and they may feel like they're constantly being judged by their peers and teachers. This can lead to insecurity and anxiety, which can manifest itself as obnoxious or mean behavior.
* They may be trying to fit in. In some cases, students who are obnoxious and mean may be trying to fit in with their peers. They may feel like they need to act tough or arrogant in order to be accepted.
* They may simply be immature. Some students who are obnoxious and mean are simply immature. They may not yet have developed the social skills that they need to interact with others in a positive way.
It's important to remember that not all people in school bands are obnoxious and mean. There are many students who are kind, respectful, and supportive of their peers. However, the reasons listed above can help to explain why some students in school bands might exhibit obnoxious or mean behavior.