Fonts showing in Font Book but not in Finder
Apple does provide additional fonts as optional installs that can be downloaded if you want. From the linked Apple Support document, Baloo is one of those.
https://support.apple.com/en-us/HT210192
If you have Creative Cloud, then you have access to Adobe's font library: CC apps can install any font for their own use directly from Adobe Fonts, independently of macOS's font management.