Because in contemporary North American culture the expectation for a company is basically sociopathic behavior within the law. But the expectation for an individual person is ethically aware and polite behavior in the face of public scrutiny.
Too many people playing poker games instead of building a world where we all get better lives.
I expect companies to not act ethically. In other words, I think of myself as a realist and this just seems to be how companies are going to act.
On the other hand, I expect them to act ethically. Meaning ethical behaviour is the behaviour that I demand from them.
Like when a parent says to their teenage kid who refuses to study for an exam, "Well I expect you to get an A". They don't expect that, but they do expect that of them.
Maybe these two sorts of "expect" get shorted out when corporations enter the picture? On the other hand, perhaps the expectation of a corporation in both senses really is sociopathic behaviour. All that "duty to the shareholders" crap...