Non-Player Characters

It's got to be the Varrock cleaner, only just winning (?) over the Varrock stray dog as the most useless NPC in the game.

According to  the RS Wiki, the cleaner's job is to "help cope with the large number of ashes that often littered the streets of Varrock". 

Really? Because all I ever see this guy doing is leaning on his broom around the east bank. The only times I've seen him sweep up ashes were when someone was trying to collect them for herblore. He rather enjoys pushing his broom around the Varrock east bank. I suppose he's cleaning up all that dirt and dust we adventurers track inside (read that with heavy sarcasm). 

If he's really looking to do his job of ash removal, he might want to move his cabbage across town to the west bank and the GE, you know, where people are actually lighting fires.

Another interesting debate is who is currently the richest NPC. A couple years ago, the hands-down favorite was Saniboch, to whom you paid 875 gold to enter Brimhaven dungeon. With the addition of the achievement diaries, the entry fee is waived when you wear the KAD gloves. Alathazdrar, the demon butler, may be near the top of this year's list with his whopping 10k gold salary, but not everyone has a servant. Personally, I'm choosing the fruit tree patch gardeners and the 25k gold they get (in papayas) to keep an eye on palm trees.