Aren't online sales also a factor to consider when we think about regulating fireworks? Difficult one...
IMO much of this comes down to 'being an adult' and in my observation many people in charge of cars and credit cards aren't.
A sentient, responsible adult isn't going to think thatit's a good idea to let off weapons-grade fireworks next door to people who might not want / like / appreciate them.
Banning (fireworks, alcohol, death metal, cigarettes, insert choice here) has the effect on these large children of making them believe it is cool to get hold of said banned item, and flaunt it.
So the in the end all that really works is to be brought up well and develop a sense of social conscience. Is that really too difficult for all of us?