In the book they did something where a bunch of people show up to a place to try to show their belief on something, and try to change what is going on in their comunity. In the book I think it was called a demonstration. the definition of demonstration is: a public meeting or march protesting against something or expressing views on a political issue. So this can relate to things that people are doing today. For example there is one in brazil called "The anti-world cup protest."
I choose these two picture because it shows that together, things are stronger. But alone things are weaker. So when people do a demonstration it would benefit more with a lot of people than just one person. Like how a rope is more stronger together than just one string. And it could benefit the most when it's together, than alone.