I'm confused about the Uncarrier

Help me understand this new fee arrangement cause this sounds like horse shit: As a T-mobile customer you will pay $70 a month for your plan plus $20 a month to cover the phone subsidy. If you cancel after 8 months you pay the remaining $319 for your iPhone (for example). If you wait out your two years, you own the phone. As an AT&T customer you will pay $70 a month for your plan and no charge for the subsidy. If you cancel after 8 months you pay a cancellation fee of $300-400 dollars. if you wait out your two years you own the phone. Is it just me or are you paying an extra $20 a month on T-mobile for functionally the same thing?