Probably wearing eyeless cowls like Batzarro does, too, as blindfolds so that they won't be able to squawk about the Batcave's location. This could get awkward - I can picture them stumbling around blindly, tripping over the stuffed penguins, shattering the display cases, with poor Batman hopping around impotently in the background, shrieking at them to be CAREFUL, please! Back a bit! No, no not that far - AAUUGH! That was Ming!