I installed postgresql with the rpms that are available from the postgresql official repository. I'm not familiar with distro-builder, can you explain what is it ? The file in your link doesnt look like my postgresql service file.
Some parts of software installed from rpms is specific to each distro There is a PostgreSQL RPM Building Project that takes care of maintain the repository.
There is nothing wrong with the installation path you have followed, but if you had installed from source you could have ended with a different start script. The source is maintaned by the Postgres Core Team.
