So, one party by default overcharging for their product and the other supplying it at cost makes you feel that when the one party puts their product on sale, a temporary condition at best the product suddenly become equivalent?

Then you should also compare the Chrombooks with second hand large format laptops, old servers on sale with new ones and so on.

Chromebooks 'on sale' are an entirely different class of product than raspberry pi's, they are larger, need wall power, have built in batteries and screens, are in general still more expensive and do not have GPIO.