Registry Cleaner and File Extensions

Running CCleaner on an XPpro machine, the Registry Cleaner wanted to delete a bunch of "Unused File Extensions" under HKCU\Software\Microsoft\Windows\Current Version\Explorer\File Exts\... These included such common items as bmp, gif, jpeg, jpg, pcx, tif and tiff - and dozens of others.

Was this because there aren't any of these on my C: drive? All my data is kept in a separate partition (F: drive, actually) and includes a mass of picture files of one sort or another.

And would it have mattered if I had I let it?

I noticed in "jkinqqm"'s thread started 18th Dec about his (failed) attempts to run CCleaner on his D: drive, that the forum contributors think that CCleaner does not look at any drive other than C: Now that huge HDDs exist and lots of us use multi partitions, my last question is whether it should? (That is, when CCleaner's most excellent programmer has the time or inclination!)