On November 18, SEPTA will give $1 credit to those who buy their tickets on board the train. As we know, if a ticket is purchased on the train, whether the station has a ticket office or not, the rider is charged an additional surcharge (or what SEPTA calls it, the on board fare).
Soon, riders who pay the on-board fare will be able to take their receipt to a ticket office, and when they purchase their return ticket the same day, they will get a dollar off the ticket price. Of course, this directly markets to the occasional Center City bound rider, as most ticket offices aren't open in the afternoon or on the weekends.
For more information on this new fare policy, please read the following article: http://www.philly.com/inquirer/local/20071027_SEPTA_puts_strings_on_surcharge_rebates.html