What did the presumably-a-journalist have? He wasn't used to looking for marks—it hadn’t really registered when she came in. He’d have to get a look when she left. It might be a newspaper, or maybe a notebook. It was such a non-earth thing to do—he’d have been slapped if he looked at a woman’s hips instead of her face, but the ponies seemed to use these marks for identification, to the point where it was apparently expected that they would be scrutinized. That could be why the two doctors didn’t cover their hindquarters, so that anyone could recognize their specialty.