Corporations are entities and should be considered entities, not people under the law. There are times when it is necessary to pierce the corporate veil to punish individuals who commit illegal acts either with or without corporate knowledge or support. Even though they are composed of people, corporations should not be treated as "persons" for legal purposes.
Corporations were and are created to protect the interest of the people starting up a company. Corporations are seen as entities to protect the assets of the company, and to protect the owner(s) who have invested a lot into it.
Let's say you and some friends decide to start a business. To form a corporation would be the best option, as far as saving everything you've built in your life. If you went in as a Partnership, and then get sued, your personal assets are at risk. You could lose your house, savings, everything. If you form a corporation your life before this business will be protected. Corporations have to be treated as people in order for the courts to assume liability on their part if there were any kind of lawsuit. Just because there are perks for corporations, and some companies take great advantage of them, does not mean every corporation should suffer.