Note that everything is relative and marginal (“compared to what, for what increment?”). I don’t think “favor” is the right word for surplus from trade, as it goes in both directions, and is unmeasurable. If you buy a car for $66K, the dealer makes $11k profit, but also has effort and employment costs, so that’s not net. And you’re getting more than $66k of value in owning the car (or you wouldn’t have bought it—you’re not intending to do a favor, just making a trade that benefits you and happens to benefit them). So they’re doing you a favor as much as you doing them one.
Which is to say that the “favor” framing isn’t very helpful, except in motivational terms—you may purposfully take a worse trade than you otherwise could, in order to benefit some specific person (or even a group, if you’re weirdly altruistic enough). But most economic analysis assumes this is a very small part of trade and work choices.
The key insight in figuring out the work and purchase decisions is that most things have different values to different people. A given hour of effort in an endeavor you’re relatively skilled at (“work”) is worth some amount to you, and some amount to an employer. It’s worth more to an employer than to you, and your pay for that hour will be between those values. For simplification reasons, and measurement difficulty, and preference for stability, it’s usually traded in bundles—agreement to work 40+ hours per week for multiple weeks. That doesn’t change the underlying difference in valuation as the main transactional motivation.
Note that everything is relative and marginal (“compared to what, for what increment?”). I don’t think “favor” is the right word for surplus from trade, as it goes in both directions, and is unmeasurable. If you buy a car for $66K, the dealer makes $11k profit, but also has effort and employment costs, so that’s not net. And you’re getting more than $66k of value in owning the car (or you wouldn’t have bought it—you’re not intending to do a favor, just making a trade that benefits you and happens to benefit them). So they’re doing you a favor as much as you doing them one.
Which is to say that the “favor” framing isn’t very helpful, except in motivational terms—you may purposfully take a worse trade than you otherwise could, in order to benefit some specific person (or even a group, if you’re weirdly altruistic enough). But most economic analysis assumes this is a very small part of trade and work choices.
The key insight in figuring out the work and purchase decisions is that most things have different values to different people. A given hour of effort in an endeavor you’re relatively skilled at (“work”) is worth some amount to you, and some amount to an employer. It’s worth more to an employer than to you, and your pay for that hour will be between those values. For simplification reasons, and measurement difficulty, and preference for stability, it’s usually traded in bundles—agreement to work 40+ hours per week for multiple weeks. That doesn’t change the underlying difference in valuation as the main transactional motivation.