Yes, you do. If you have a household insurance, the insurer normally covers you for stolen objects in the event of burglary or attack. However, what about the most frequent case - losing things? Also, very often the expenses which are to be reimbursed are under the excess amount, typically amounting towards CHF 200.
In addition, CardProtect provides a further crucial benefit: Just call and CardProtect can have your lost/stolen cards (also SIM cards!) blocked and makes important personal data, such as your ID number, available to you in an emergency.