Lugano to Chiasso (with S-Bahn)

This might be my first time to ride S-Bahn... S-Bahn is a local train, which stops at every station.
A train for S-Bahn is newer than rapid express trains such as IC (InterCity) and RE (RegioExpress), which is my question... (My current answer to the question is because a fee for a rapid express is the same as one for local train.)