The fact that paying those inflated prices after the initial purchase isn't an option is already enough to turn me away from buying any of them (or even the laptop itself).
I think it's more (and it's not just Apple playing this game) that the entry model/price is horrifically under-powered. It's there to hook you in on the price, and that's it. The rest of the pricing is then designed to pull you along the upgrade ratchet.
i.e. You've paid the absolutely necessary $249 to get the 512Gb... then it's only $200 to get an extra 512Gb. Once you've overcome that first hurdle, the 2nd looks almost good value.
$999 Starting Price. tempting
+$249 +265Gb SSD (and a 8th GPU core)
+$200 +8Gb RAM (to a reasonable 16Gb)
+$200 +512Gb (to a nice 1Tb)
So that's $649 for a 768Gigs of SSD, 8 Gigs of RAM (and a GPU core). Cost of 1Tb gen-4 and a stick of RAM is about $200