Nobody seems to notice this, but using quotes stops you from error of using {foo:"bar"}. In JavaScript, {foo:"bar"} is not an Object, it is a code block containing a labeled code block with the label, foo, in it with a string, "bar". This is what {foo:"bar"} really means in JavaScript:

    {
      foo: {
        "bar";
      };
    }

Labels cannot be strings, so quoting them will help you catch this error earlier.