Those prayers are meant to be imitated by Muslims because he is our uswah hasanah(spiritual role model). Also, since he was married, when he went to his wives, he felt that in those moments of intimacy he was closer to earth than heaven so he sought forgiveness for that. Also, there are other mundane matters like when one is in toilet that one cannot mention God’s name although we pray before entering the toilet to seek Allah’s protection against spiritual and physical impurities. We also pray for Allah’s protection against Satan before intimacy who can influence the soul of future child. We also remember Allah while being in the markets which are away from God.