I was just on Facepunch official #1 and the server list said 0 people but once I got in there was about 30 in game. I noticed official # 2 said 0 as well, but I didn't check that one yet.

Edited:

I just played on official Facepunch # 2 for a few and it's the same thing. List shows 0, but there was 33 in game.