The date on the milk I bought was a 'use by' date so officially it should have all been binned by midnight on the 4th March. It would seem that since the 4th March I have been slowly poisoning myself - strange 'cos I've never felt better! Seriously though there are some foods that will deteriorate very rapidly after the use by date and become harmful. Though as you say G what nose can't detect a bad bit of meat or eye/nose detect the mould on a loaf of bread.
However a 'best before' date is purely for guidance and so long as food doesn't show any obvious signs of deterioration it is perfectly ok for it to be sold and of course consumed. Where the plums were concerned they had a best before date, a couple of them were bruised and needed to be binned, the remainder were in peak condition for the dehydrator having nicely ripened. So why don't the Richards at Morrisoffs understand this?