I mean, they get to decide when it's finished, if it's stable and there's enough content that people are playing hundreds of hours then they can say that that's the basic experience and if people want more they need to pay for it, in the end it's even worse than just not having paid DLC and increasing the price as the game gets more content and life becomes more expensive.
Not as if there was anything new to doing that, Minecraft cost about 5$ for the people who bought it as soon as it was made available, now you don't even get the mobile version for that price.