I'm saying there's a difference between earning and benefiting from.

Selling others labor isn't legitimate earning when you get a higher share of the labors value than the laborer themselves.

You can earn by deploying your own labor to facilitate transactions between other laborers, such as by running a job fair, that's completely legitimate, good, and creates value. You can't just take 90% of someone's wages, or rather, you can, and many people do, but it's theft.

Because it's not your labor to sell and if you take part of the proceeds for yourself, that's theft.

Because they believe in the Marxist labor theory of value, where apparently it's theft if someone else uses your labor to make something more than you could make yourself, not understanding the fact that that's not how labor markets and total human collaboration works to make something more than the sum of individuals.