Whilst you made valid points, not sure we need them repeated with contradiction. 'how do you police that' By your own admission... 'The police always seemed to enforce the no standing in the passageway behind the seats when the game is in progress'.
This has become an issue in a poor layout upon a terracing complete with seats. Another view point, is moving between the seats holding hot/cold food & beverages not equally as dangerous?
As for the last statement - Pompous. 'part of the ground that is designated as a no standing area' Oh, please! No provision has been made, the safety certificate will state as much - the turning of a blind eye approach has served the club well. But, your ideal seems to be 'it's alright, just not where I sit'.