The problem is that, for better or for worse, people do not have full freedom of contract by law. There are volumes upon volumes of laws and regulations limiting the kind of financial contracts, for example, that you are allowed to enter into. Every bank has a massive compliance department dedicated to making sure that they abide by those rules.
You can't just ignore these rules by making a system that executes contracts automatically. The judge will simply order you to make the other party whole. Then, if the law allows it, he might hit you with a massive fine for breaking the rules.
You can't just ignore these rules by making a system that executes contracts automatically. The judge will simply order you to make the other party whole. Then, if the law allows it, he might hit you with a massive fine for breaking the rules.