Actually, as a minor aside to this one, a (female) mate & I used to regularly travel to watch bands.
We'd book a cheap hotel, & whoever booked would say something like: 'I'd like a twin room please, for myself & a friend'.
We'd quite regularly get given a double instead, especially with big chains - no big deal, except I snore. No one ever greeted us on arrival with 'aaargh! Two women! & I've put you in a double! Do try not to, erm, mess the sheets up'.
However, dh also used to regularly book twin rooms for gig-going, with his brother.
He once got a double room by mistake, & when two blokes turned up - the receptionist was overcome with confusion & embarrassment. She hastened to change the booking & upgrade them to two singles - even though they explained that they were brothers & actually, had no real problem with sharing a bed - they'd be out all evening & then sharing a bottle of Scotch back at the hotel, so no big deal.
Going from other friends' experiences with the hospitality industry, it does seem to be a not uncommon theme - two men cannot be left to share a bed, unless they've specifically booked a double. But two women can.
Not sure if it's Queen Victoria syndrome, or concern for the sheets. Very odd, anyway.