Sure, but this is all transparent to the user. Apple heavily pushed iCloud backups and doesn't mention that it throws any data security out of the water. You hear iMessages are secure and then you accept the "use iCloud backup" question that appears right after you get your device. Except now your messages aren't secure.

Apple did a great thing by making iMessage secure by default. They should do a similarly great thing by making iCloud backups secure or by making it very obvious to the user that they are not secure (and what that means for your other "secure" data).