I agree, it should not be difficult for programmers on this forum.
Even I can write a batch file that does exactly that.
It compresses and encrypt the wallet, then ftp to a private server on web.
Yes batch file is a good option for linux and Windows, not sure if you can make one for mac too.
It would be very easy to create a program that does this, but I can just imagine the post...
"Download this .EXE and run it to back up all of your wallet.dat files."
If it's open source, I don't think there should be a problem, as people download miner .exe's and different altcoin .exe's too.