“Misusing paper wallets is related to that. Not all wallet software is designed to support paper wallets. People who don’t understand this have managed to delete money before, by importing a private key that was exported, making a partial payment, then destroying the wallet – not realizing that the change didn’t go back to the same key they imported.”
Yikes! Which wallet software is liable to do this?
Most people don't understand the privacy implications of reusing bitcoin addresses and thus see the failure to reuse addresses as a bad thing. Those sophisticated enough to be using paper wallets are certainly sophisticated enough to understand that if address A sends money to address B, the change does not got back to address A, but rather to address C (another address in the same wallet as A).
This is a failure to communicate the core principles of the protocol, not a failure of the wallet software.