I grew up in a small suburban area where a lot of my learned behaviors came from being a mall rat. Since that was the major place I socialized (in the arcades), you quickly learned how to try and signal you're not willing to talk or engage with people. Mainly because malls had a ton of smaller stalls staffed with sales people who would immediately try to pull you aside if you even gave them a side glance and try to sell you a phone plan or other things.