Regarding Missing/Deleted DVloper Apps

Why aren’t most of the apps created by DVloper (Dennis Vukanovic) on the App Store?

In case you don’t know, here are the apps that created by the developer that are not on the App Store:

Slendrina (2013 Paid Version)

Slender Man: Stands (Free and Paid Versions)

Slendrina The Cellar (Paid Version)

House of Slendrina (Paid Version)

The Child of Slendrina

Hotel Insanity

Robot Hunt

Slendrina X

Granny 3