Why is Wanderlust Letters only avaliable in Adobe Spark?

I found my new favorite font "Wanderlust Letters" when playing around in Adobe Spark, but then I noticed that the font is not avaliable in other Adobe programs (i.e. Illustrator and Photoshop). Is this a miss?

I found another post saying that it can be purchased from an external site, but it seems weird that it is included in Spark and not on other Adobe programs.