If I am wrong about this, someone will surely correct me.

I don't know how many high school marching bands did what you describe. But if they did, their inspiration was likely the 27th Lancers. The 27th Lancers were a founding member of DCI and were based in Revere Massachusetts. Unfortunately, they folded in 1986. They finished 2nd to the Blue Devils in 1980 in Birmingham.

Their uniforms were all based on British military uniforms and each section, the hornline, drumline, and color guard had a different uniform. With the Lancers, it was actually the hornline that wore the Aussie hats.