Total upsell, they are just trying to re-coop any loss on the vehicle and/or trade-in value they are giving you.
If you see the vehicle you like, take it, walk away, never return to that dealer unless there is a serious problem. They'll resent it if they had to give you a good deal and take it out on your vehicle.
I bought all that stuff, and that's how I decided to call myself DuMouixe.
Although, the fabric protectant works well, I believe they used Roll-Off, 303, Maybe 3M. But no, frippin way worth $500... I called back the next day and they said, "We already had them install it, yeah, right."
The paint sealant, had to take it back 3 times for them to remove the water spots, in the process they dented and scratched the car, etched the glass, then cleared over their bad work to hide their mistakes.
Then never made it right.
I've been bandaging my hemmoraging paint, waiting for trade-in time.
Then they just put you on perpetual ignore and say things behind your back like, "Disgruntled Customer"
I'm not even mad, just wish they would be more honest in their endeavors towards all.
Does that answers it? of course, that's just my opinion.
$500 buys alot of waxx.