I'm using ArcMap (10.3.1) to connect to Postgres (9.4.5), which has Postgis version 2.2.0 installed. Create/Enable Enterprise Geodatabase wasn't used in this database. It's just a connection to the database. The connection itself works fine, but I get duplicate feature classes for each Postgres table. Only difference I've found is that first one has ability for address geocoding and second one looks quite normal. Also the first one has function Create Feature Class, and the second one Create Layer. The Postgres tables were created with FME 2015.1.
When dragging the feature class to ArcMap View, they both contain geometries and exact same attributes.
I checked that this shouldn't be related to Id, since I'm using objectid attribute, and ArcGIS recognizes it as Object ID data type.
View in the catalog: