When the offer is $X now or $X/36 for 36 months, it's clear the seller is paying the financier, but that doesn't mean the seller will offer a discount for current payment.
Some do although, especially when you poke them about it. You see it often with cars where you offer all cash vs the %0 financing option, you can often get a discount that way. The $2000 in interest you were going to pay implicitly through the inflated price of the car goes away.
