Ben 10 is the new He-Man.Since 2006 "the Ben 10 franchise has grossed over $2 billion in retail sales in Europe, the Middle East and Africa (EMEA) and has sold 100 million toys worldwide".
Maybe Bandai doesn't know how to deal with toylines that aren't billion dollar megahits. They usually do Dragonball Z, Ben 10 and Power Rangers, all insanely popular shows.