Edit:
Sry for the low image quality, I rescaled my screenshot to get it below the 100kb media upload limit of my instance and it looked fine in the gallery. I should have outsourced my upload...
And even with the apps, you're still able to pay for premium versions, like Reddit Premium for instance
Could be that despite the app costing 0 euros up front, it can't be labelled truly free because micro-transactions exist