Probably shouldn't tell border patrol you're doing unpaid labor in a country you're visiting. When speaking to authorities it's best to say the absolute minimum required for the encounter.
Statements like these make me happy I live in Europe.
If you live in Europe you'll need a visa to work in the US. You want to live in the US to not need the visa.
Well, I live in Europe and work for an American company and I don't need a visa. In general, the USA is a very nice country to visit but for long-term living I prefer the EU.