I don't think you realize that we don't disagree here.
My advice was only meant to reflect what to do in cases of true reimbursements.
The original post asked specifically about unmarkedup subcontractors.
It was that particular type of item that i was specifically responding to.
I should have made that more clear in my response.
You're exactly right on the lemonade and robot examples.
But if I get hired to run a lemonade stand, and the person who hired me would also like some linens used on the table (not something I normally provide)--- well, I might say, "I can do that but it will have to be ordered special. Would you like to pay the linen bill directly or should I order and you just reimburse me through my invoice?"
If she chooses to simply reimburse me, I can absolutely take care of the expense the way I describe. Ditto if I hire a staffing company to professionally pour out the lemonade.