Maybe because footy fans are easy targets who offer almost no resistance, and can be hearded like sheep and can also be wound up just enough for the CCTV to "prove" that they were being violent.
I have seen my mate arrested for dancing on a train seat, yet I have seen people smashing up cars, looting shops, and burning out buses, and the coppers have stood there and watched them do it
Imagine if a group of these idiots set off inside a football stadium?
Could be absolute carnage.
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