When we dont have server then only we can use the reader.
We can use the server for the sharing purpose. you told you have server in company then why you will not used. Server will help us so much. like permissions, editing, sharing, update, email subscriptions etc.
Please make use of server.
Do users who are just viewing the data need licenses? Currently using desktop version, they can view my reports using the free Tableau Reader. If they need a license just to view the output from Server, at $1,000 per user then I do not have the budget to get them the licenses.
If they can view reports without getting licensed, then I will look into using the Server - I do not 'own' the server, it's in corporate.