Will be treated literally the same way, as in costing the price of a house to reach maximum theoretical power and shoving the shop into the player's face more and more as they grow in level? I very much doubt it as well.
But there's a non-0 possibility that Blizzard sees how much raw dosh they make with Immortal and decides to sprinkle a bit of it into D4. Timesavers such as faster leveling. Guaranteed Legendary on your next boss kill. Pay to reroll stats with an increased chance of perfect ones. There's tons of ways they could add that sort of thing while still saying "hey you don't directly buy power!".
I'm not saying such is exactly their nefarious plan. It's very possible D4 comes out with the shop being just a few cosmetic sets, mounts and such, which I wouldn't have a problem with so long as there's also a bunch of these things earnable in-game such as in WoW. But I do think Immortal's scummy business model should leave us wary as to their monetization going forward.