Why are some fonts available in Storyline but not Rise?

you can import and use any font in rise using the custom font feature in your course settings. here's documentation on how to do it.

Two considerations with fonts and Rise. 

1. Licensing: many of the system fonts and other fonts you have access to in other apps may be licensed for those apps or operating system
2. Web fonts: the fonts in desktop apps are usually true type fonts or something else. In Rise you need to use web fonts.

As noted above, you can import your own web fonts. Google Web Fonts is a good resource for open source web fonts where you don't need to worry about licensing.

Thank you, I am aware of how to import fonts, I was interested in why they were in some Articulate products and not others; however it looks like Tom has answered that. Cheers

Thank you Tom, unfortunately it looks like some fonts will need to be purchased for Rise for licensing reasons as you have mentioned.

You may find comparable fonts at Google that don't require licenses. And the font foundry may have a web font available for their fonts. And of course, there are a lot of font converters online that will convert to a web font.