People watching, observing people and their interactions, usually without their knowledge, is something I have done a few times.
Do you enjoy doing that
Not necessarily, for me it is a subconscious activity they partake in everyday without even realizing it unlike others that do it for a hobby.
Do you love subconscious activity ?
I wouldn't say I love it, no. Just something that tends to happen sometimes. I guess picking up on idiosyncrasies to try to guess at another person's story just comes to all of us really at times, subconsciously.
Yes sometimes I do that
Also, eavesdropping, at times, accompanies people watching activity.
Wow
Although, naturalistic observation should not be confused with people watching. 
Really they should not