You can map to physical pages without masking it by a virtual page if you use the fully qualified url like http://somesite/somepage.aspx instead of the ~/pagename.aspx
In the latest version it will not create a virtual page that masks a physical .aspx page on disk. In previous versions it would create a friendly url mapping and this would mask the physical .aspx page when using the ~/pagename.aspx syntax. However, you could go into Url Manager and delete the friendly url that masked the physical page then it would just link to the physical page.
Hope it helps,
Joe