title: Why can't we connect to firestore on node.js server using just public apiKey
body: <p>In my React project, I am using firebase public apiKeys to access services like authentication and firestore. So it means we are not required to use <code>admin-sdk</code>.</p>
  <p>Then why we need admin-sdk to leverage firebase services on server environments like node.js? Won't public apiKeys do just fine?</p>
  <p>I mean client side is exposed to public while servers can be accessed by only the managers and developers of the organization.</p>
  <p>Please explain me the reason for this.</p>
  <p>Thank You!</p>