The worst examples are, of course, things companies would not do. Like your grocer not selling you food, or your landlord not renewing your lease.
Which should tell you something: the worst people say about governments is that they behave the way they do -- the worst thing people say about corporations is how terrible it would be if they didn't behave the way they normally do.
Do you know of any private firms that disappear people who speak out against them? Governments have been doing that for millenia, but I can't think of a single private firm that has done so. The US government has a military and intelligence budget north of $600 billion and operates secret prisons around the world.
Was that the worst example you could think of?
"The government could make me disappear."
So could a private firm.