Then it turns out that she was using Workaway, which is like AirBnB or Uber but for foreign labor on tourist visas. They don't tell you that you need a work visa to work in another country [1], but you almost certainly do anywhere you go, not just the US. The woman in the story was working in exchange for accommodation, which is legal for citizens but not for aliens: work permits and visas exist to deter illegal immigration. She didn't have intent to immigrate illegally, but the scheme under which she entered the country was illegal, and she confessed to it in her statement to the border guards.
The real bad actor in this story was Workaway, and I'm surprised they haven't been shut down yet. They offer an alien labor arrangement that is almost certain to get you detained if caught with the wrong visa, don't give you advice on visas, and aren't there to help if something does go wrong at the border. I doubt there are many countries who welcome their alien labor arrangements, either.
[1] "Workaway is a listing site that enables contact between members, we are unfortunately unable to arrange or advise on visas. There are so many countries with different regulations or laws for different types of volunteering activity, so we would suggest directly getting in touch with the relevant embassy of your destination. It is the responsibility of the host and/or volunteer to make sure they are within the law." https://www.workaway.info/en/stories/workaway-for-newbies-co...