[sgent]

The only reason I can think of is that Stripe (and Paypal) have much lower credit standards for merchant, making it easier to sign up for. In addition, they have more marketing in the consumer space, and have done a lot of work to make it easy to integrate with online tools.

Most credible merchants would do better with a bank or similar processor, assuming they have some experience in programming interfaces (or at least troubleshooting them).