I doubt that the police would concede they were picking on a cultural minority. As with many events I suspect the police look at evidence of previous behaviour and make a risk assessment on the strength of this evidence. A classic example of this will be the championship football match between Leeds and Milwall. I have no doubt restrictions will be in force, on the basis of previous behaviour.
If police were not to give advice and trouble occurred no doubt they would be pilloried in the press for neglecting public safety.
john