I thought that might just be Amazon resellers capitalizing on marks being too lazy to go off site at first when they were $280 at Microcenter (still crazy expensive). [0] Then Adafruit had them for the same $350! [1] And it really does seem to be driven by the ram too the 4 GB model is only $130 (or $104 at MC).

[0] https://www.microcenter.com/product/702590/raspberry-pi-5?rd...

[1] https://www.adafruit.com/product/6125?src=raspberrypi

Just like eBay, an Amazon listing for a certain price does not mean the item is actually /selling/ for that price -- especially with badly-coded dynamic re-pricing algorithms hooked into listings these days.