In a recent Behavioural Scientist article, Dr. Vanessa Bohns articulates the ways in which we influence others without even realizing it. Through her research studies, she found that even strangers who compliment each other can have a greater impact than they intend. As she states in the article:
"This research dispels the misperception that in order to get someone to pay attention to you, you have to wave your hands around and shout. Ad executives may need to pull out all the stops in order to grab people’s attention, but you don’t. You already have it. You are a person, not an ad or a tweet, and people are wired to notice other people. More than that, they are wired to wonder what other people are thinking, and to adjust their own thoughts and behaviors accordingly. What this means is that you are quietly and subtly influencing the people around you all the time—without even trying, and often without realizing it."
Dr. Bohns seems to be inadvertently referring to social norms here, which are well-known to behaviour change agents but less visible to the general public. For a more nuanced perspective on social norms with plenty of original research, you might consider checking out Dr. Bohns' book:
You have more influence than you think: How we underestimate our power of persuasion and why it matters.