Capitalism introduces a concept called a legal personality, an abstract concept consisting of an entity. These entities are supposed to be in charge of cooperations, be liable under law and so on. It separates the subject from the object, and so creates the illusion of personal non-liability.
Capitalism didn't create that legal concept, governments did.
Indeed. All capitalism really is is the ability to retain the excess value created from trade. Banks, loans and all the other financial stuff arises from that but corporations are a government created fiction. It can be called more properly corporatism though it might legitimately be called fascism if that term hadn't completely been distorted in it's usage (by the left, no surprise).