I remember the first time I saw Jackson Academy, I was amazed at what they did! So few people, but they all did EVERYTHING. I'm assuming from the "academy" part that they have the resources (money wise) to do many things, but they really used everyone they can make shows the way they do.
I'm from a large school, so we often have people who don't get to do things. Practices can be inefficient if people aren't really focusing, because a couple of people talking can turn in to a disaster. Large bands and small bands have difficulties with different things, but they both have difficulties.