A quick survey of internet pages about seasoning hamburgers shows that most recommend seasoning the outside of the burger. Fewer recommend mixing spices into the ground beef as the patty is formed. Are both methods satisfactory?
Years ago, packets of "hamburger helper" contained directions to mix it into the raw ground beef for making burgers. Today, the videos I find about hamburger helper are not about hamburgers, but rather about mixtures of ground beef with other ingredients like macaroni and rice where the ground beef is cooked loose, not formed into a patty.