Even power users are still vulnerable to exploits that are executed by a site you're visiting or image/video you're viewing. And exploits that take advantage of

Even power users are still vulnerable to exploits that are executed by a site you're visiting or image/video you're viewing. And exploits that take advantage of privilege escalation don't just protect multi-user systems, they protect you if you're running as a limited user or if you're using UAC. It's a scary world out there for everyone, even if you don't run plugins in your browsers.