@Wingflier
You're interpreting the SotS team's actions as "they made a bad game, then charged the consumer to fix it." I can understand your distaste for that model, indeed, I share it. In the case of SotS, though, I don't think it fits what really happened. The SotS team released a fairly simply, beer and pretzels strategy game. I would fundamentally dispute the claim that the game was "bad," it was reasonably bug free and fairly well crafted, it was just a very basic strategy title without much complexity and I (and clearly you) didn't find it particularly appealing. Kerberos (the developers) did vigorously support the title, adding free content, patching it up, etc, but free updates were never going to elevate it above what it was: a basic, light little TBS game that wouldn't appeal to you or I.
In releasing expansions, however, they virtually created a series of sequels, more depth, more mechanics, more races, more technologies, more of everything with each one. It wasn't a case of fixing a broken game, it was a case of taking a very simple, basic game and turning it into a very complex, deep game over several iterations. It's a subtle distinction, and I couldn't blame you if you didn't see the difference, but I think it's a meaningful one. The post-release support for each expansion has been vigorous as well, with new content added, new tweaks, and integrated feedback from the community. Indeed, prior to seeing Arcen's frankly insane support for AI War, Kerberos' support of SotS was some of the best developer support I'd ever seen.
Of course, at this point, the complete collection is regularly on sale for $10 or less, so it's hard to make the argument that anyone's getting ripped off anyway. Just treat that as the base game, in many ways Kerberos seems to regard it as a sort of SotS 1.5 themselves, and ignore the humble beginnings of the project.