We live in Hershey, PA and at the town square, the NYE fireworks were going off about 150 feet AGL. With 100' bloom, that doesn't give much time for the embers on the bottom to burn out. Fortunately here, it's a rail bed and parking lots. Under the BGW trestle with a breeze blowing at all, there's just shoreline to catch the embers.
Having a handline deployed ahead of time certainly save a lot of ground this time. Hopefully they do it each time in the future, plus look to get shells exploding higher in the air.
Our July 4 fireworks in Hershey actually got cut short this summer, I just remembered. The hillside that they are launched from caught fire, took a while to extinguish (dry few weeks heading up to July. Probably could have sprayed the field down an hour before the show, but I'm not a professional so I won't attempt to judge).