The thing I like about React is that I don't have to think about the DOM. As soon as I see "el: #id" it's basically over for me. I don't want to think about DOM elements, or at least minimize my exposure to them. And it's not just that I don't like to think about the browser DOM. It's that I don't want my UI coupled to the DOM. Obviously your UI will be coupled to the DOM to some extent, but React minimizes that. Wha…
There's literally only one of those, to tell what element in the HTML to bind the root Vue instance to. Vue doesn't require thinking about the DOM.
It's the same sort of thing as React's basic tutorial (https://facebook.github.io/react/docs/getting-started.html)
ReactDOM.render(
Hello, world!,
document.getElementById('example')
);