there is a fence that keeps locals without "a reason" for being there out. The vendors have stalls that they rent from RCCL to sell their things there. My husband and I bought some really interesting things there, but you do really have to bargain.
Yes, some of them can be aggresive, but if you know how poor Haiti is, you can understand why...it's a must for survival.
If you don't want to buy something, say no, thanks and move on. They will get the hint.