Is this proper that your site shows a sub site for every made board?

In our site contents it shows a sub site created for every board (along with 3 new security groups). Is this expected? If so, how do organizations typically organize these so a giant list isn’t created with all their boards?

KanBo creates a SharePoint WebSite for every board along with a KanBo Document Library in it and 3 Security Groups that correspond with the 3 Groups in a KanBo Board. The intention of this is to allow you to extend KanBo functionalities by additional Document libraries or build your own dashboards using the KanBo App Parts. They can be inserted like web parts into a WebPart Page or a Wiki Page that resides in SharePoint. There are 4 App Parts available at the moment: Activity of the last 30 days, My Involvement (how many cards I am working on in a board), Users Activity and card distribution on lists in a certain board.