Earlier quoted context omitted.
People in the US were not haggling for anything less than a car in the decades before the internet.
Not true. As recently the 90s expensive niche gear like a pro audio or video stuff was almost always subject to price negotiation, especially if you were a repeat customer or indicated an interest in possibly purchasing other stuff. It still is to some extent. In general the more knowledgeable the dealership/salespeople, the more likely negotiation is possible, especially if you present as a knowledgeable customer so…
As far as I understood, it wasn’t in the interest of the big retailers to spend time haggling with individuals.