Think of it this way: there is no opportunity for an new entrant into this market almost globally. Stripe's fee is low enough and its API is super easy to use and the brand is well loved by most ecommerce companies. A new entrant will have to go up against this enormous amount of goodwill that Stripe has accumulated. The only danger to Stripe is if a major bank decides to get into this space. I work for a major bank and let me assure you that the technical expertise , market savvy and wisdom to pull off a new venture like this just doesnt exist in banks.