Hello. This is what I think of King Dedede and why he did what he did in the games. This is not about the anime, it's just the games.
Chapter one: Kirby's Dreamland
King Dedede saw what Nightmare and his minions were doing. They were spreading darkness all over Dreamland. The King knew how to stop them, however. He just became King, and he knew he would get a bad reputation. But he stole the citizens' sparkling stars, and battled Nightmare and his minions. The darkness stopped spreading and receded.
...
one week later
King Dedede heard that someone was visiting Dreamland to see what he could do about the food problem. Dedede knew the visitor would find out that he had the Sparkling Stars.
"I need to give these to some of most powerful and loyal subjects!" Dedede said. He gave them to Whispy Woods, Kracko, Fololo and Falala (known as Lololo and Lalala at the time) and Kabula.
One day later
The King could see the visitor come up Mt. Dedede with 4 of the Sparkling Stars. "Oh no..." Dedede said, "he can't be that strong!"
After a long and gruesome battle (it took one minute) The visitor had gotten the King's Sparkling Star and was returning all the food to Dedede's subjects.
"Oh no..." Said the defeated King, "I hope he knows what he's getting into."