Because corporations are not citizens. Corporations consolidate many orders of magnitude more financial power, skill at executing political leverage, and focus compared to individuals. They use that power to manipulate government in ways that are biased towards corporate need, but which don't balance other concerns. This is bad because it puts corporate power and influence very out of balance with personal power.
The aims of corporations are often dead-set against the wishes of affected citizenry, the company's employees, sometimes even the corporate executives (wearing their "private citizen" hats).
The aims of corporations are often dead-set against the wishes of affected citizenry, the company's employees, sometimes even the corporate executives (wearing their "private citizen" hats).