I voted "the bench" because I am already a very-well-practiced people-watcher. After all, that is what you do when you are alone in the restaurant, or at the mall, etc. Because you have no one with you, you just sit and watch other people. And, I have spent many, many, many hours of my life doing just that. Of course, when you are people-watching, you want to remain unnoticed. So, you actually try not to stare...
I should also say that I have spent time with other people eating in restaurants, etc. - I haven't been a total loner all of my life; however, I have no doubt spent as much or more time alone than with someone else in these places...
So - it kinda "fits" -- sitting on the bench, watching ( staring at? ) people.