These bypasses are typically not for when are the only user and also the administrator. Sudo here is not really for securing your machine: as others have said, if an attacker gets to your personal account, it is game other. It is mostly a tool for you to avoid fucking up your system by mistake.

These bypasses are useful if you want to get root access on a machine you are given some, but not all administrative rights, like a shell and a few sudo commands, for example to restart a service.