They hide away their identity to stop people speculating about bcash's centralized mining operations. Those miners didn't come from the Moon. They were mining bitcoins before the fork and now they mine bcash.
They don't hide away their identity, they simply choose to not mark the blocks of an anonymous digital currency they mine with their id, the same way as nearly each and every bitcoin user chooses to not mark their bitcoin transactions with their id. Just because some miners choose to advertise their mined blocks doesn't mean it's some kind of "standard" or desired behavior. Even if all the other miners were marking their blocks it would still impose absolutely no obligation onto these miners to do the same. You can't seriously blame people for not being brainless sheep that only do what the others do.
