Bad because for the dot com company I work for, we use cookies to make sure we don't show users 'helper' tooltips more than once per 30 days and cookies is one of the better ways of doing this. It also helps us anonymously track a user location to show better search results, user currency etc.
There are many bad ways a website can use cookies, but by using a plugin like this, it'll ultimately just ruin your own user experience.