i do this every where, you never know when someone will rob/mug you or someone close bye its better to be aware of your surroundings than to be oblivious to the world....... we go out to a bar and what not im always watching the scene and the people i usually can tel when things are going to turn into a fight by watching across a bar
just last night on my way home i noticed 2 young kids walking up the road by my house and thought they were acting weird watching around so when i came to a stop sign and then went forward i keep a look into rearview and watched them launch rocks throw a window on a house and run, called one cop i knew on duty and said they never got a call from house and noone was home tho