My suggestion: Personalized ticketing, strict entrance controls, video surveillance and consistent prosecution with reporting and a lifelong stadium ban. It will definitely take a while, but at some point even the last idiots will learn. Or at least the idiots can set off their pyros while watching football in their own living room after they’ve been caught.
Anyway, I’m wondering why this hasn’t been done for a long time. The clubs pay a lot of money and have sporting disadvantages, see point deduction, for the stupidity of a few complete brains who have nothing better to do than setting off pyros in the middle of a crowd or making other shit. And the other 99% in the stadium, the real fans, also suffer from it.
I would actually be interested to know how high the clearance rate for pyrotechnic offenses really is, especially when it involves bodily harm, and how high the compensation is that the caught perpetrators have to pay. That should actually ruin people financially; if it’s pure stupidity, no insurance company will probably pay.