The pyrotechnics go beyond New York. In Los Angeles, Baltimore, the Bay Area and Hartford, Conn., residents have taken to social media and neighborhood message boards for weeks to complain of fireworks. In Boston, police said they received more than 1,400 calls about fireworks the first week of June compared with 22 the year before…

A variety of theories have grown.

With New York’s annual fireworks show and smaller neighborhood displays called off, some have wondered if more commercial pyrotechnic devices are being sold underground. Fireworks company associations have disputed that charge, saying distributors keep a tight grip on products.

Others have proposed that more residents, many stuck largely indoors for months, have resorted to setting off fireworks out of simple boredom. A lot of loose gunpowder and a bit of fun and escape in the pitch of night.