[MC-62138] "#PLAYER" Appears on Sidebar

When adding a fake player, prefixing their name with a # is meant to prevent them from being shown on the sidebar, which does not occur as of 14w29a:

/scoreboard players set #PLAYER OBJECTIVE 1

Linked issues

~~Disregard as duplicate, got beaten by:~~ MC-62134

Actually that is unrelated, as it concerns other players being displayed. Odd that their players with # labels are not being shown, confusing.

#PLAYER being displayed when it shouldn't.