Lets say you want to organize your pictures into folders for organizational purposes. Or keep all your downloaded PDFs in folders like "eBooks" and "Whitepapers" and "Academic Articles" etc. That way they are organized the same way no matter what app you use to browse them. This is much better than how, say, Photos app works... in Photos app you have one long list with all your photos sorted by date and you can't change how they're sorted nor move them anywhere else, except delete them. You can add them to albums but you can never see a list of whatever photos have not been added to albums yet.
Also you can't rename your photos without a file manager, or even SEE their names for that matter. It's a joke!
Have you seriously never used a computer or its file manager?
What do you do if you want to free up space on your device, without a file manager? What do you do if you want to back up your saved games from Infinity Blade 3 to a different folder so you can delete the app temporarily? You can't, not without a file manager.
What if you want to download an MP3 of your band's latest practice to a folder on your device so you can listen to it without redownloading and without polluting your iTunes library with crappy practice tracks? Once again, without a file manager you, sir, are screwed.
Yes, there are annoying, kludgy apps that semi-accomplish these tasks in various non-standard and lame ways. But it's no replacement for an iOS Finder.
I'll admit, not everyone is smart enough or uses their device enough to benefit from a file manager. But it would not harm those people if it was there.
Personally though I think even stupid people would benefit, because files and folders makes a lot more sense than "my naked photos that I deleted last month went where?!"
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AMEN. oldmacs you are my new best friend.
Let me add to what the above genius has eloquently pointed out: iCloud PhotoStream *compresses* and *alters the resolution* of your photos. It does not transmit RAW images.
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Dude, real panoramas stitched from high resolution DSLR images can be 2GB in size, each. I have panoramas on my Mac that are 40GB in size.
