In newspaper stories, one finds the phrases "he said" and "she said" in almost every paragraph. That's because objective journalism requires that virtually everything be attributed to someone. Putting a "he said" or "she said" in so many sentences can be difficult for beginning reporters, not because they have a problem with attribution but because they have a problem with using the same words all the time. They want to write "he replied" or "she explained."
The word said is favored in journalism because it is simple, short and objective. Other than that, reporters are encouraged to find different words that mean the same thing. If a building is called an auditorium in one sentence, it will be called a facility in the next. I don't know if it is a human trait, a cultural trait or just the fact that in English we have so many synonyms and so many slang expressions, but most of us don't like to repeat ourselves. We seem to enjoy finding new ways to say the same thing.
While watching televised football games recently, I have heard announcers use the following words and phrases:
between the tackles
inside the numbers
In each case, they meant virtually the same thing: running straight ahead toward the goal line. Yet you rarely hear an announcer actually say "straight ahead."
In football, running the ball north-south is considered a good thing, but in our speech and writing we tend to favor going east-west, avoiding straight-ahead words like "he said" and "she said."