Because Sprint has there own leasing arm.
Lease:*GS7 $25.99/mo./line for 24 mos. GS7 edge $30.50/mo./line for 24 mos. For well-qualified customer with new-line activation. 50% off promotion isn't reflected during checkout. Bill credit of $13 on GS7 or $15.25 on GS7 edge applied w/in 3 invoices. Credit ends at 24 mos. or upgrade whichever occurs first. Does not apply to discounted phones.*GS7:*©2016 Samsung Electronics America, Inc. Samsung, Samsung Galaxy, Galaxy S, Galaxy Note, Samsung Gear VR and Samsung Pay are trademarks of Samsung Electronics Co. Ltd. Use only in accordance with law. Other company and product names mentioned may be trademarks of their respective owners. Screen images simulated. Appearance of devices may vary.