Earlier quoted context omitted.
well first off they have many customers, I'm one of them, that use and love their product. Second, anyone with an established merchant account that would like to add a recurring payments front to it is in the market for recurly and not as much stripe. Not sure about Samurai, but Stripe is an aggregator of payments which can lead to problems down the line because credit card companies don't like to deal with aggregato…
Established merchant accounts are expensive. Why pay those merchant account fees, and on top of that, pay another set of fees to be able to do recurring billing?
Recurring billing is a whole separate issue. I've rolled my own before and realized how much of a pain it can become. Using recurly allows all non devs on my team to handle all the subscription and recurring problems without me having to build anything.