I have been going to the same gym, a large one, for 18 months.  I go the same three days of the week at the same time.  There are three people I know from other venues who I see there once in a while.  However, there are some I see regularly who I do not know.  When I am on the treadmill, I look around (not plugged in, am I) and I take attendance.  I notice the same few people on treadmills, one on a bike, and another who is always stretching on the mats.  Others I note moving from one location to another.

I wonder if they do the same?