No, you don't need WebParts. You'll load the XLS file from a web link like http://sharepointserver/folder/subfolder/file.xls. It's really simple as it looks.
The only thing is that you'll need to check where the file will be stored to get the correct web link.
QlikView webparts are used to embed QlikView content within a MS Sharepoint portal. When QlikView objects are embedded the green white and grey association is maintained between the objects, so if you change a selection in one object the other (related) objects change, just as they do in any QlikView application. The webpart license exposes/provides a connection/configuration option from inside SharePoint to QlikView. The concepts is, if you wish to access QV objects, like a chart, guage or container object etc, you will use the Webparts to achive this, because it's quick and very easy to do it this way. So with web-parts its about QlikView content being displayed in SharePoint rather than SharePoint content in QlikView. You should be able to access SharePoint list content without using QlikView Web Parts.
You can also use a URL web-part (non- QlikView compent) to access an entire QlikView document and display this in SharePoint.
Anyone accessing the QlikView content regardless of "how they access the content" requires a QlikView license of some sorts.
Hope this help ?