This seems like a necessary component of any "effective acquiring bank"[1] because of where the liability falls. In the event of fraud, Stripe can get hosed and they need to protect themselves.
I imagine they wouldn't have taken the step of lowering their payout delay from 7 days to 2 days unless they were confident in their fraud detection abilities.
Can you elaborate on what about WePays fraud protection is better? Am I dead wrong?
Note: in no way affiliated with Stripe, just once considered starting something in this industry.
[1] I'm defining Stripe and WePay as "effective acquiring banks." I guess you can call them ISO's too. They're positioned somewhere in the web of words - but bottom line is that their the ones that find merchants that need to process cards.