For better or worse, JSON is becoming a major format and it is a first-order Postgres data type. You need to add the hstore extension if you want it. So it make

For better or worse, JSON is becoming a major format and it is a first-order Postgres data type. You need to add the hstore extension if you want it. So it makes sense for people needing/wanting JSON and are not aware of some extension called hstore. In other words, it is about improving the ease of use.