Originally Posted by burningvegeta

-He absorbed him to remove the risk of fusion, plus he recognized Piccolo's great intelligence when guiding Gotenks though the battle against him. Piccolo was just as much of an obstacle as Gotenks was.
-They were two sides of a coin, one cannot exist (true form) without the other. His idea was for them to be one once again.
-Buu does not absorb when he feels like it he didn't absorb anyone on the look out after his departure from the Hyperbolic Time Chamber, nor did Majin Buu when he destroyed countless cities. Super GohanBuu is a perfect example if he cannot kill his opponent he resources to absorbing them.