I don't take mine off, for the simple fact, I wear glasses, and it's a pain in the butt, to carry, and put them back on.
Hey, I'm a speccy too, with full-face lid.
They go in the lid, along with gloves and headover, which gets slung on the bars while I go pay.
Cor, the insolent laziness of youth today, eh!!!
As for the Knight thing - ALL knights are courteous, chivalric, upper-class twits who are gentlemanly to the point of stupidity, so they will remove their helms as a matter of course.
And Mars bars? Pah - Commoner food!!!!