Chrome lets you take your Chrome stuff with you, so you can always have your Chrome experience on all of your devices. Adding new users to Chrome isnt intended to secure your data against other people using your computer, since it just takes a few clicks to switch between users. To add a new user to Chrome, go to Options (Preferences on a Mac), click Personal Stuff, and click Add new user Check out our latest Beta blog post for a few quick tips.”]
Source: https://chrome.googleblog.com/2011/12/get-your-personal-chrome-experience-on.html