"dealer financing" is an umbrella term for the dealer's finance office acting as a "loan broker" and shop around the customer's credit profile to find any bank willing to lend the money. The eventual underwriter for the loan may be the auto manufacturer's finance arm (e.g. General Motors Financial subsidiary or Toyota Motor Credit, etc) ... or ... it may be a non-automaker bank such as Chase or Capital One. Whichever one the customer ends up with depends on the particular credit score.

None of those financial entities are making car loans as a "loss leader". It's the reverse situation where both the dealer and the underwriting bank make money and the interest rates are high enough such that the banks pay kickback commissions to the dealer for funneling the loan to them.

A more accurate way of saying this is that the dealer is using incentive money to buy points (as is available in the mortgage market). You can ask dealer to apply that to the price of the vehicle instead. Many dealers already offer that kind of choice in their advertisements already (cash bank or no interest financing). Which way works out better for you depends on the terms of the loan etc. It's all the same to the dealer though.

Another trick in the industry, is the "price the dealer pays". This is mischievous, as the dealer does indeed pay that price for the car. However, they receive incentives quite often, in terms of kickbacks for sales made. So they dealer can gleefully say "This is what we paid for the car", whilst in parallel not indicate "Well, we received $5k as a kickback from the manufacturer later".

The manufacturer often also has monthly blitzes, discounts of the month, which the dealer will not really inform you of. After all, that's extra profit if they can trick you into paying full price.

In the early days of the internet, there used to be excellent services to discover all the discounts the dealers had, so you could a proper assessment of their actual cost. Thus, you'd be able to haggle with both eyes open.

For Canadians, The Automobile Protection Association (APA), https://apa.ca/ is legit, and offers such a service for a fee. Not sure what Americans might have. Or who to trust there.

Knowing what the car actually costs the dealer, is immense power when negotiating.