I find this disturbing in a way I can't quite quantify. Kids should do things, not just appear to do things because they're clever about outsourcing to someone worse off.
Hiring and managing someone else, while being the point-of-contact with your clients, is doing a thing; it's a very useful life-skill, in fact. There are other useful life-skills they might be better off not delegating away the learning opportunities for, of course, but usually "chores" are less learning experiences and more "I used to do this thing, but now you're old enough to take the load off me."
Of course, if there's no life-lesson, why not just cut out the middle-man and have a local chore marketplace where kids from all around the neighbourhood can directly bid on the contract to mow your lawn. (Mostly kidding, but that'd be somewhat interesting for people who don't have kids, and don't need a full-on gardener.)
I tend to think that doing physical work, understanding what's involved, is educational, informative, and motivating. A significant part of the world does work with their body. It's important in having empathy for other "classes" (assuming your kid gets an "information worker" job). Related or not, it's important to also learn how to do a job you may not like well, to pursue excellence in one's work.
Instead of my kids accumulating more junk, they learn the skills of hiring and delegating.
Don't want to mow the lawn in this heat? Use your allowance to somebody else to do it. As long as the job is done they will earn their allowance.
I just need a way to make sure they're not outsourcing their homework or paying somebody buy them alcohol.