You began the thread with the title, "Just Wondering ....... Who do you work for?" The answer is, "it depends."
It depends on who you are talking about, the circumstances at the time and the relationships involved. There is no single answer because expediters seldom work for a single person or entity at once.
Regarding an expediter taking short runs, the answer to the question "who do you work for?" is the same. It depends.
It depends on who you are talking about, the circumstances at the time and the relationships involved.
Example: Diane and I used to lease our truck to a large carrier with centralized dispatch (employee dispatchers). We now lease our truck to a large carrier with decentralized dispatch (self-employed agents).
If a dispatcher called us with a 55 mile run on a Friday morning we would likely decline it because the favor we would do would take us out of the dispatch order, diminish our changes for a good weekend run, and the favor would almost certainly not be repaid because the dispatcher has no power to repay it with a good load later on.
If an agent called with the same 55 mile run on a Friday morning, we might very well take it as a favor to the agent because there is no dispatch order and the agent has the power and incentive to repay favors.
It's not about the run. It's about the realtionships. Where favors are returned favors are granted.
Changing the subject just a bit, let me say to new readers that not all short runs are bad. Many short runs pay very well. A short run may be the only money that can be made on a given day.