They're using @autotrade and @afk so there's more than just merchs.
And, their population is not 500, it's 111, 130 tops. Wich means they have around 10-30 players on at the time and they pretend they have 110, I dont see how that's fair. Besides I've seen and heard of servers being de-listed from RMS Top SHR list for this.
I can give you screens but youll only see lots of players sitting in every town.
However if you stay for 2-3 hours everyday, and you keep coming back, you'll always see them in the same position. Some are Novices, some aren't. The fact is that they dont log in, and when you message them the system tells you they're on Auto-trade mode and they wont reply.