Unfortunately a number of your colleagues misuse terrorism laws and claims of obstruction to prevent people recording their behaviour. CCTV does also have uses as those who are aware of the case last season of one of our younger fans who was falsely accused of disorder and had his case thrown...
And to clarify (with the exception of covert operations) when asked a Police Officer is obliged to give you their name and their station. They may also provide their collar number.
I don't know about Sussex plod but some may remember a game at Peterborough a few years ago where a number of OB had very clearly removed their ID and were spoiling for a fight.