Moving Saved Web Page Overwrites .htm Files

I'm using Windows XP Pro SP2 I have encountered what seems to be an undocumented feature of the file move action.I saved a web page including associated files from either IE7 or Firefox2.If I move the associated files folder to an other location the .htm file moves with it. Why? Who told it to do that? Where is the user configurable option for to link a file to a folder? Where is the global system behaviour option to enable this non standard file system behavior? If you move the associated files folder to an other location which happens to contain a .htm file with the same name (eg the very common index.htm file), the undocumented behaviour described above will still occur and the file will be overwritten without ANY standard file conflict warning and without any user choice in the matter.