The ecommerce sample application is far older than the responsive/touch initiative and does not take into account these options.
Since the data service it was based on was discontinued by its owner, the eCommerce sample app is no longer supported and is left in only as a code example of Telerik controls integration.
If you need to start reworking your pages to provide responsive design I advise you start from this help article: http://www.telerik.com/help/aspnet-ajax/mobile-support-and-responsiveness.html.
You can also find useful this sample application on responsive design: http://demos.telerik.com/responsive-web-design-aspnet/default.aspx.
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