Does anyone else think that there is too much deception and ulterior motives for people that do not have hearts and therefore really shouldn't give a care? I mean you have Marluxia and Larxene rebelling, Axel pretending to be on their side then turning against them, Axel killing Zexion so that Saix could advance in the ranks (?)...it's just funny to me.

No hearts means no emotions which does not mean not wants. Saix plan in advancing ranks was revealed in days as a part of Lea's and Isa's plan that was made before or shortly after they became nobodies.

Oh! I thought Axel kill Zexion because Zexion knew that he kill Vexen and it wouldn't be good for him if the organization knew that.

Well, they are nobodies, as in they are empty shells with no emotions or hearts. So of course there will be deception in the Organization. Marluxia betrated the Organization just so he can become the new leader and takeover Org. XIII. Larxene betrayed all because she doesn't want her heart back because apoarently having a heart is "painful". Saix ordered Axel to dispose of Zexion all just to move his rank up, and Xemnas, in a way, was only using the other members to obtain KH and would probably go off and betray them after he succeds in that goal.

 

So yeah, there was a lot of deception in the Organization.

Just because they don't have emotions doesn't mean they can't show what they remember the emotions to be. Thats why the Organization are so special. They remember what it felt like to have a heart, so they can portray emotion as they like. But, as they cannot actually feel the effects of the feelings, they would have no problem with betraying and killing their fellow members. This is also why Axel never really seemed sad in 358/2 Days.

Okay I agree and I get it but I still just find it funny.