If this is true it'd be brilliant. I was prepared to adopt your theory myself, but figured I should at least google it first and that brought me to this:
https://www.history.com/news/july-4-fireworks-independence-d...It says John Adams wrote:
“The Second Day of July 1776, will be the most memorable Epocha, in the History of America...I am apt to believe that it will be celebrated, by succeeding Generations, as the great anniversary Festival…It ought to be solemnized with Pomp and Parade, with Shews, Games, Sports, Guns, Bells, Bonfires and Illuminations from one End of this Continent to the other from this Time forward forever more.”
It seems he was advocating for celebratory gunfire! The article goes on to say: "[fireworks] would become an increasingly important part of the festivities in the years to come, as public safety concerns caused cannon and gunfire to be gradually phased out of celebrations."
Doesn't disprove your theory (cannon and gun fire would probably be even more effective than fireworks) so I'm adopting it. I'll be sure to spread it around the next time I'm attending a fireworks shew! It also suggests we should have learned our lesson about celebratory gunfire centuries ago, but I guess some people are so slow that even after all this time they still haven't caught on.