It does not matter as a consumer, no one saves anything because all costs are passed on to the purchaser. If it is not credit cards, then some vendors soak people for shipping in base rate costs.
In my experience in doing business with plastic, I view the cut by the vendors like Paypal or the credit card companies as a business cost. They employ people too and it is a service which makes my selling simpler. They itemize, they provide a degree of protection from fraud and I can manage accounts quickly.
Cards like Discover which I use, pay me cash back at various rates, so I do earn the exchange back too in some ways.
There is also the reality that card rates are a business expense, so therefore a deduction on income tax.
What I dislike are the bean counters who refuse to use cards because it costs them a few dollars. The rates are around 1500 dollars per 50,000 in transaction income. Yes that is a very nice firearm, but the deduction in taxes means I have a part of that to purchase what I want to. Sellers who antagonize buyers end up having less sales to other vendors who make things easy for the consumer. In weighing the business end, I do not see the mania some sellers have in paying a charge to use a service, which in most cases they pass along to the consumer. It is though money and you find out what people really are like when it comes to a few pennies. I have had people who were extremely polite go animal when they thought a transaction they paid for went to another seller. Other times, for instance, I had a very sweet lady make a mistake by electronic paying 6000 dollars for a 60 dollar transaction. She simply alerted me and I refunded and could not have been more nice about her mistake, as that was a great deal of money to make a mistake on.
After my credit card number was stolen in using a California vendor, I almost always now shop through store fronts like Ebay and Amazon, even if they are liberal, as they protect the ID. It all comes down to though, that no one is forcing a seller to sell things and no one is forcing a consumer to buy things. I make a point of using the system in place as it is efficient and cost effective, in someone in the hinterlands can market globally. I benefit from it, and I do not complain that other people in these services charge for it, as they employ people who need jobs too.
I never thought I would be a person who thought cash and checks were a hassle, but when you run businesses it is not really feasible or time effective to use paper. Granted on ADC or other projects if people offer cash, I do not turn them down, but in e commerce it is cards with costs, even when the vendor charges me a 1.50 extra for a service.