Certain controls just add bloat to a page. Like the RadListView is a GREAT control to use inplace of the asp Repeater, but I find I often don't use it (or limit it's use) because it brings down 99.9% useless client scripts. Most of the time, especially in Sitefinity its a server-side render-only control. Just used to show data...we don't need ANY client manipulation.
The ListView is a pretty lightweight component, which injects only two scripts on the page responsible for its proper operation and drag and drop capabilities:
WebResource("Telerik.Web.UI.ListView.RadListView.js", "text/javascript")]
WebResource("Telerik.Web.UI.ListView.RadListViewItemDrag.js", "text/javascript")]
The Telerik AJAX controls offer not only server-side but also rich client-side API and capabilities and for that reason it will be a huge breaking change to implement the requested functionality.