As far as I remember of the rules (having never paid much attention since I don't have a merchie class character) all AFK-chatrooms and vending whatsits go on the sidewalk.
It's just that heRO is finally growing out of the "bottom half" of the middle fountain for pront... Namine finds it a great inconvenience (and a dirty trick for some merchants) to open a shop right on top of another existing shop... thus effectively blocking out the shop for who knows why... No matter how Namine tries to scroll around or change the camera angle, shops are just blocking out each other by stacking directly on top of everyone, it's hard to see all the selections possible.
Zoom out to normal range and the shops should not overlap each other. The sidewalk expands further south, people are free to place shops there.
A few years back, I played on a server with over 10 times more players and they also had this sidewalk rule, needless to say the sidewalks were packed, still it's nicer than having them all over in the street.
Just another mindless question from Namine... in her old server, the sidewalk rule also exist... but they allow the "fountain area" as part of the sidewalk. Does the fountain area permit shops for heRO?
(Using Mr. Bloody's screenshot as reference, the fountain area is where the flower gardens begin, so it would be behind all the NPCs)
Mhh Lumi here, And i clearly remember setting my shop on the sidewalk, and going autotrade. I cant explain it and I know the rules. But i can assure you i didnt make my shop in the middle of the road.
I'll take a look tonight. There is only one way (that I know of) to move an @autotrade shop.
Moving an autotrade shop to put the merchant in trouble is of course an offense and will be dealed with jail/ban depending on the previous history of the offensers.