Crew can refer simply to a group of friends, unrelated to crime or violence.

He is not referring to an entire group of people.

As a noun it can refer to a group of people.

Intense debates can build up over which of these terms to use when referring to a specific group.

This is how the term band first came to refer to a group of musicians.

The word "school" could refer to either a group of fish or a place where children are educated!

Murder is a term used to refer to a group of crows.

Later workers used the name to refer to a specific group of organisms.

The term is also used to refer to a group of mountains formed by such a structure.

The term seal is used to refer to a diverse group of animals.