It’s important to offer a variety of payment options as well as credit and debit cards for customers who prefer them, and PayPal is the obvious alternative that many retailers now offer.
It could also be about convenience. Even if a customer can use a credit or debit card, the effort involved in inputting numbers (especially on mobile) means some prefer to use other methods.
It’s also important to match the payment methods offered to local preferences. Preferred online payment methods will vary between markets.
While shoppers in the US and UK generally use card payment or PayPal, there is more variation elsewhere.
For example, ELV, a kind of direct debit payment, is the most popular method for German consumers. IDEAL is a similar method that is popular in the Netherlands.
Other options include deferred payment or credit options, which may help with bigger ticket purchases such as electronics and automotive. These can be offered directly by the retailer or via solutions such as Affirm. Ecommerce websites can’t offer every possible payment option, but by providing choice they can cover most preferences.