It looks like SEPTA is trying to encourage more travelers to purchase weekly or monthly passes. They’ve recently introduced a site called SEPTA Pass Perks and according to the marketing message:
With a weekly or monthly SEPTA Pass, you’ll receive discounts and other goodies to some of the best destinations in the region. Just have a look around the website to see all the places that accept Pass Perks. Then head out on the town, on us.