The “viewer list” is a bit of a misleading name for it because it actually lists people connected to the chat room, not people watching the stream (although they mostly overlap in most cases). The viewer count tells you how many people are actually watching.
In order to not show up on the list, you can read the chat on a justinfan username, which does not require a password, but also cannot send any chat messages. (justinfan followed by some random numbers)