Ahhh... but see, there's the rub! The 'evidence' is not 100%, it does not say that it is conclusive that Caylee was dead in that trunk, according to many defense experts! When Baez and his team tell them the evidence is weak... who do you think they are going to believe?? When their PI's tell them that they are close to finding a LIVE Caylee, who do you think they're going to believe?? When Casey refuses to admit that she KNOWS where Caylee is, and refuses to accept responsibility, who do you think they're going to believe?? I think the answer is obvious.
To believe otherwise means that they have to admit to the world that their daughter killed their granddaughter. They simply cannot accept that. Not publicly, anyway. They MAY know in their hearts that Caylee is dead, that there is no hope of bringing her home alive, that Casey is going to prison for murder and will likely be there for the rest of her life... but to the public they have to maintain their hopes and continue to support their daughter.
Would we, as rational people do that? Hard to say, unless one is faced with this situation. I might THINK I could... but I don't really know.
When you get right down to it... what they are doing is prolonging their agony... the time will come when they have no choice but to accept it... but for now... they are holding on to every shred of hope they can, because that's all they have, really. Casey is lost to them, Caylee is lost to them, and even IF they know that deep down... they won't admit it to anybody now, and maybe never. Being angry with LE, with TES and Tim M., with everybody who tries to reason with them... that's the fuel that keeps them energized. Yes, it is ridiculous... yes, it is painful for US to accept.... but it is what it is!