I'm sure not everyone would want to go through that process for every transaction, or know how to for that reason for an average user like me. As the Bitcoin community goes that will include not so tech savy people too, so us not so tech savy people can have top of the line security without responsibility on us.
typing in a username and a large entropy password (for security) and then typing/scanning a destination address. takes the same physical time and process as typing in /scanning 3 QR codes/priv-public keys