And corporations can stand for things. They can have missions and use funds to effect speech in support of causes that align with their beliefs.
There are organisation forms that are a lot closer to being just a group of people working together, like co-ops and firms maybe. I'm not entirely up to date on all options in English-speaking countries (which will vary of course, but the Dutch Maatschap is probably as close as you can get to a company that's just a group of people.
So the Dutch just go ahead and call a group of people a "mash up"!
> If the First Amendment has any force, it prohibits Congress from fining or jailing citizens, or associations of citizens, for simply engaging in political speech. If the antidistortion rationale were to be accepted, however, it would permit Government to ban political speech simply because the speaker is an association that has taken on the corporate form.