I can't speak for everyone, but I have only had 3 customers (out of about 275) ask me about credit cards in the last year. The only thing that made any sense for me was PayPal. There is no fee to set it up and anyone can pay you, with any card. The fee is small, in fact, the largest charge was $275 and the charge was $6.35. I have a link on my website that I direct customers to and you have your money wired directly to your bank account in a day or two. It works great!
Of course, the drawback is that the customer has to be registered with PayPal, or be willing to get registered. If they want to use the card bad enough, they will.