Concerned Ape (Stardew Valley): I swear on the honor of my family name, i will never charge money for a DLC or update for as long as I live. Screencap this and shame me if I ever violate this oath.
Each expansion more or less adds extensions to the game the fundamentally expand on the mechanics and systems within the games. I’m okay paying for that, personally.
Why? Rimworld is a great game on its own. The DLC are basically large and detailed mods on their own. If you don't want to pay for the DLC, don't do so. Most of the mods don't need the DLC.
Or just find a good sale on them when Steam does their thing 4-6 times a year.