>I think there's an element of that, but it seems to be partly
>practicality (it's hard to operate a Striker Unit with trousers on,
>though Adolfine Galland manages it) and partly cultural (in a couple
>of instances, non-military witches and retired combat witches are
>shown in similar states of {un}dress). It's never explained in any
>detail, but from context it seems like it's just a witch thing.
> Nobody remarks upon it on the infrequent occasions when the witches
>are out and about among civilians (for instance, in the episode where
>Lucchini, Yoshika, and Shirley go shopping in Rome).

I've been going on the assumption that the earliest known witches had to cast a lot of magic in a hurry before they'd finished dressing, and then had to spend so long convincing everybody who saw that no, being sans-trousers was a perfectly normal witch thing to do that it stuck.

That, or the rise of magic was reliant on the lack of the invention of shorts.

~Silv'
I could go on, but I won't