@mherrmann’s article on PayPal vs Stripe is worth reading:
…offering PayPal was a good decision: Even though Stripe is the default option, two thirds of fman purchases are now made with PayPal. From feedback, I know that some people simply can’t pay by credit card. Thus, offering PayPal significantly increases fman’s (small) revenue.
I recall @andrey having a similar experience with PayPal.
You may get some value out of the Hacker News discussion of the article:
My experience running Pinboard (which offers Stripe and PayPal as payment options) has been that PayPal is indispensable if you want to collect payments from people outside the United States. There are also common situations where Stripe doesn’t work (for example, the customer only has one credit card and it’s declined) but PayPal does.
Stripe is far more pleasant to use and implement, but continue to see around 2/3 of my payments coming through PayPal.
My own thoughts from back in 2014 http://www.elstensoftware.com/blog/2014/08/18/paypal-versus-stripe-customer-survey-surprising-result/
I think this was @mherrmann’s original post on this work My experiences with PayPal for SaaS
Link doesn’t work anymore 
The link is now fixed!
I was skeptical about Paypal necessity, but to my surprise, while paying for the code signing cert my business CC did not work. Why - no idea, all provided information was correct, and still. The checkout screen had a Paypal link tho, which I promptly used and it worked with the same card.
So yeah… as much as CCs are ubiquitous, Paypal is still a good backup channel, at the very least.