Why would anybody enter a girl's chat room, sit there saying nothing and tipping nothing, and expect the girl to put on sexy show for them for free? Are people really this entitled? I think it's fine to be passive in the chat-room, since typing is indeed a pain in the arse, but if you are just passively staring at the girl without tipping, then you can't compain if the girl doesn't want to entertain you.
Some girls do seem to give very little attention to the VR cam and are clearly more focused on their 2D chatroom elsewhere, but I guess they have to prioritise whatever stream is actually making them money.