People tend to shoot a lot of fireworks in the summer. They do here anyway. Between Memorial Day and Independence Day, there's a good chunk of the planet getting blown up in some festive displays. I'm not complaining, it's fun to shoot them off and they're pretty to look at. But summer is a spooky season. Remember Silver Bullet?
It's pretty common on Cybertron as well. The Sparkabots, whom shoot festive sparks are often at odds with the Firecons. Decepticon monsters who breathe sparking fire. It's a true yin and yang on the battlefield. The heroic Autobots vs the evil Decepticons. Valor versus venom... and the prettiest fireworks display.