It's not limited to just video games. Fans of The Simpsons will know that two of Homer's friends/co-workers are Carl Carlson and Lenny Leonard. People do this in real life too, I have seen people named Jack Jackson, John Johnson, etc., don't forget that boxer George Foreman named all six of his sons after him (George Foremen, Jr., George Foreman II, George Foreman III, etc.) and even named his daughter Georgia.