I get what you're saying here. McDonald's, the franchiser, makes money on rent. But they're renting to McDonald's franchisee's (at least in part, likely a majority of it). Even if they're renting out to third parties, those third parties are making money largely from service, which is rendered via labor.

So the service is performed by labor, and the service makes the revenue to pay the rent and pay the labor, QED, rent is paid by labor.

McDonald's franchisee's are paying their rent with labor. It's not like the franchise is getting fully assembled big Macs delivered. The labor needs to assemble the parts to make the whole.

Without labor, they would have no product to sell, since it's not feasible to cut out the on site assembly of the food while keeping it as fresh as it is.

Yes, a nontrivial part of revenue is in materials, and there's a mark up on the sale of those materials when sold, but the majority of cost is for the labor of putting everything together.

On top of this, there's plenty of non-McDonald's examples of the same. I work in IT support, almost all of my work is service, where I go in, either in person or remotely, and perform corrections to get things working normally. There's plenty of industries that have similar models, where there's little to no production of things that you're paying for, and the vast majority of the payment is for labor.

Finance, tax prep, handymen, carpenters, welders, programmers, factory workers, delivery drivers.... The lion share of revenue is directly from labor.

With food service costs are generally split between labor and materials, since the raw materials can be rather costly, but for many other workforces, labor is the main revenue.