Earlier quoted context omitted.
Corporate personhood has a very long history in the US. https://en.wikipedia.org/wiki/Corporate_personhood
people =/= person. All people are persons, but not all persons are people. I enjoy Stewart, Colbert and Oliver as much as the next person (vernacular usage, not legal), but they've done a lot of damage to the national discourse on this topic.
People is a plural of person (persons is also a plural of persons); all persons are people just as all people are persons, the two terms are in this use synonyms (people also has a singular use.)
Not all people or persons are part of “the people” as that is used in some Constitutional provisions, but 14th Amendment due process rests on the definition of “person”, not “the people”, and in any case the Supreme Court has found that the distinguishing feature of “the people” is attachment to the national community, not natural (as opposed to artificial/juridical) personhood, so U.S. corporations are, Constitutionally, all of “persons”, “people”, and included within “the people”.