Lot more deaths from shooting a bullet into the air (do they not *realize* that it comes down at high velocity? seriously) than from waving around sparklers, in my opinion.
Who are doing this, and on what occasion? I had not heard of this, it sounds scary!!
People with no sense, and on pretty much any occasion they can come up with
I've known two people to get injured from this, both while I was a college, both times from an idiot shooting off a gun a quarter-mile away and not realizing the whole "I shot a bullet into the air / It fell to earth, I knew not where" thing. (With apologies to Longfellow - I'm sure he'd be against this too, if his arrow had hit a person instead of an oak . . .)