The RPi starts at $35. The prices you’re seeing on Amazon are scalpers takings advantage of the chip shortage. When Adafruit, for example, has them in stock, they’re at MSRP.
I mean isn't the truth somewhere in between? You can probably get one a lot cheaper than $150 or whatever it's selling for on Amazon if you don't need it today. At the same time you're right that it means something that you can't just go out to the store and buy one at anything remotely close to MSRP
As far as I can tell, the only Pi that you can reliably buy in quantity 1 at list price is the Pico.