Most, if not all, fireworks are illegal in Denver - not that that stops most people, but it does keep the sizes down. Until this month, when we've had record-setting rain (10.38" - 0.1" more and it will be the wettest month on record) we've had drought conditions for the last 10 years or so, making the risk even higher.
I'll give the kids who were shooting them off last night credit - they were in the sandy part of the playground in the park across the street - but yes, I still called the police on them. This whole area of Colorado, recent rain notwithstanding, is plagued by wildfires, many of them started by people, and I have no desire for my house to be incinerated in one of them.