I think I know where Omar's heading with this so allow me to explain the peanut plaza.
Peanut Plaza is quite possibly the saddest place on earth. I used to go there all the time in junior high school and high school to play CS and shit in the little internet cafe they have there with my buddies.
Flashforward to now time, about a month ago my HS buddies and I decided to relive the old days and decided to visit the cafe again.
Here's where the sad part comes in. When we're walking over there we noticed the exact same drug dealer who used to sell us weed hanging out in the exact same spot we always saw him in high school. Then, when we got into the cyber cafe we saw the same people we saw all the time back doing the exact same shit they always used to. I was srsly mindfucked. Either all these people knew we were coming back for that one day and also decided to come back or these guys hadn't changed at all in like 7 years.
So the reason why Omar is scared of Peanut Plaza is because it's a fucking timewarp.
Either that or the fact that dudes have been stabbed/shot there multiple times, or the asian supermarket that there now turning the already shitty parking lot into a bonafide P-Mall-esque warzone.