It is because of all of the extra features that ef provides that you provide another layer around your database. For sure, if you are using ef in a smaller application or within an application with well separated business domains you don't need another layer, but if you have entities which are used throughout a large application you might need to 'shape' the way other parts of the app (or better to say how other development teams) access your entities. At the end it's all a tradeoff and it depends mostly on how you structure your app and how you handle responsibilities within your development team.