The issue is the new iOS 7 Activation Lock, not any content on the account. Unless "Find my <iPhone/iPad>" is turned off before wiping, the device's serial number is tied to the Apple ID that was previously signed into the device. Even after a complete wipe and reinstall of the OS image, you still cannot use the device without that account's password. The setup process will ask you for that login info and will go no further unless you have it.
http://support.apple.com/kb/ht5818
The intent with this is that if you lost your device or had it stolen from you, even if you remotely wiped it, it would be worthless to anyone who may have found it.