If you view a profit on a supply basis, as "the difference between the sold value of a good and the price to produce it", then somebody living paycheck to paych

If you view a profit on a supply basis, as "the difference between the sold value of a good and the price to produce it", then somebody living paycheck to paycheck is, by definition, not profiting off of their labor. The cost of living, and thus be able to produce labor, is approximately the same as the amount they're being paid. If you view profit on a demand basis, profit is the difference between what the the seller values the good at and the value the buyer places on the good. In that regard, labor is never sold at a profit for the laborer: companies only purchase labor that they can use to produce more value than they pay for it. Framed another way, if the value of labor is the price the market is willing to pay for it, then employment is almost always a negative exchange for the worker. The value of someone's labor is the price that employers are willing to pay for it, and the price employers are willing to pay for the labor is greater than the wage the employee receives (because employing somebody is more expensive than just paying them a wage). All told, unless your definition of "profit" is indistinguishable from "money changes hands", workers don't profit from their labor.