Let these people make their choices about doing or not doing it. Don't try to defend them by taking the opportunity away.

I did this for a summer, worked my butt off, got back home, paid all my expenses with the paperwork and the plane tickets, bought a laptop and came back with about 500$. It was not much, but it was much more than I ever got the opportunity by that point to make.

The people I worked with treated me quite well. Everyone I met was welcoming and warm.

I did not manage to see a lot, but I did visit Yellowstone, had a couple of adventures, and overall was a positive experience for me.

A friend I was with did not manage too well and had a nervous breakdown at the thought of having to wash toilets.

But my point is, it can be a great experience and I don't buy for a second this feigned concern for "ooh, the poor kids are exploited". No, I think it's just job protectionism.