I used to think that about email services, too. Then one after another they changed their terms when I wasn't looking, and deleted data I thought was safely stored.
What ever happened to 'your own hard drive'? Is there some reason people can't use that for storage? I have a VPS that I use as a file intermediary. I'm highly confident that, and my backups, will be there in 5 years.
For most users, "your own hard drive" is a terrrible solution. They do not have a VPS that they use as a file intermediary (they don't even know what a VPS is), and they don't know how to keep backups, and if they did the backups would probably be corrupted or out of date.
This is the miracle of web hosted software for most users. It's also what makes Dropbox so special.
I know plenty of people who use portable hard drives, flash drives and writable optic media as a backup... I don't see many downsides in that, barring catastrophic loss (which can happen to second party storage as well, though they do tend to be more professional about being careful).
Of course, a burned DVD isn't going to let me access my file from the office and at home unless I take it with me, so there are drawbacks.
What ever happened to 'your own hard drive'? Is there some reason people can't use that for storage? I have a VPS that I use as a file intermediary. I'm highly confident that, and my backups, will be there in 5 years.