The claim in the bible of Judas as a betrayer just does not fit the way that christians would have people believe. Now, personally, I think that the story is fictional outright. However, for the sake of discussion, let us assume that the events happened more or less as described.
Christians like to say that it is proper to condemn Judas because "he betrayed Jesus simply because he wanted the money." Did he? Then why would he cast the money down in the temple and leave without it? These are not the actions of a man motivated by greed. It just doesn't work. We need a more plausible explanation for the betrayal.
One meaningful possibility is that Judas voluntarily played a role to allow Jesus to obtain a greater victory. In such a case, Judas did not keep the money because his part in the play was finished. That would leave some of the surrounding claims to be embellishments. But this would make Judas really a hero for the christian religion. He sacrificed himself and his image to serve a greater cause. Needless to say, christians don't like to think about things that way.
Another possibility is that his free will was suspended and the biblical god forced him to play the "villain." In this case, the discarding of the money would simply be what happened when he was once again in control of his own actions. For that, Judas did not betray at all. His body was used as a puppet in order to play the role of "betrayer." But it is inappropriate to condemn someone for actions that were completely beyond his control.
No matter how you look at it, there is no cause to condemn Judas. That he is condemned by people whose belief that they have acquired salvation is entirely dependent on him is truly sickening.