People don't (and shouldn't) charge based on what it costs them to provide a service - they can (and should) charge based on what value they deliver to a customer.
That said, I believe in building long-term value for a customer and I do that by not charging exorbitant fees, but it's a reasonable and potentially moral decision to charge people a 30% fee in return for "never having to worry about it".
True pricing is always somewhere between cost and value. Always charging at the high end means you are always trying to capture 100% of the value created. I think that's wrong, in that the transaction is no longer a positive-sum interaction for both participants, which undermines the basis for commerce.
Regardless, there is nothing morally justifiable about charging 30% more to do less work. The autorenew system is easier not just for the customer, but for GoDaddy.
The only reason to price like that is predatory. GoDaddy is taking advantage of various asymmetries to gouge. Which is exactly how GoDaddy does everything else, so I'm entirely unsurprised.
That said, I believe in building long-term value for a customer and I do that by not charging exorbitant fees, but it's a reasonable and potentially moral decision to charge people a 30% fee in return for "never having to worry about it".