I know this post is over 5 years old, but can you please post the example that's referenced in the previous reply so others can see it? I've noticed numerous posts going all the way back to 2007 requesting the ability to put the Group Footer at the bottom of the page, but as far as I can tell by searching through the forums, it still hasn't been implemented 11 years later. Stef probably doesn't even work for Telerik anymore. Hopefully somebody can explain her answer though -
"Knowing the sizes of the PageSettings.PaperSize, PageSettings.Margins, PageHeader and PageFooter sections, GroupHeader/FooterSection and how many Detail sections will be rendered you can resize the GroupFooterSection Height using binding"