"We" are extremely susceptible to psychological and emotional manipulation though, so it's still accurate to say that those doing the manipulation are to blame.
No matter how susceptible someone is to something, a decision they make is their own.
Trying to absolve the decision maker of responsibility for their decision is a sure way to disaster. If people at large start to feel that they are not to be blamed for their actions and it's considered acceptable to pin the blame on some corporate overlord, things will get out of hand real quick.
People in general are irresponsible. A complex world makes it harder to identify pandora's boxes lying all around. And that just amplifies irresponsibility at a speed and scale we haven't seen before.
At the risk of wandering into a lengthy philosophical discussion, this is really untrue in a non-dualistic materialistic universe, which our universe appears to be. In other words, free will is an illusion, and the decisions made by people are entirely a product of their genetics and experiences.
So if people's experiences can be strongly manipulated by corporations, then so can their behaviors. It's not about responsibility, it's about reality.