MTS .. I agree that the attitude test maybe sounds a bit draconian and maybe a tad to the ridiculous but in reality it is used by law enforcement pretty much everywhere in the world from disorderly behaviour arrests to traffic violation tickets.
When it comes to benefit of the doubt there is a high chance that the security officer will stop and question and if the person seems to be approachable and friendly then a greater chance exists to gain permission than someone who begins shouting the odds.
I believe DS use this approach a lot in determining entry to the establishment they are guarding.
As regards perception from a distance I didnt think of it in those terms and I suppose that is a useful insight ... I have seen and heard some woeful instances though that border on the ridiculous ... one where a person was made to remove a less than inch sized glock keyring. again this must come down to the perceived threat by the security officer and of course as in most UK legal and enforcement agencies , common sense and discretion are allowed. The t-shirt at the main post I cant fathom other than an attitude failure!