There is no other way for these famous online shopping sites if they want to extend their market but to accept cryptocurrencies especially bitcoin. This is going to happen, although we do not know exactly when. The use of bitcoin will probably grow double or triple or even more every year and so e-commerce will have to start considering acceptance of bitcoin as payment.
With the amount of customers they have and if there was that much pressure from the customers to start accepting bitcoin they could have already done that by now,they do know what their customers wanted and i am sure that they might not be getting that much request from their customers but i hope they will start accepting at a later time,i hope some of the major gambling sites starts accepting bitcoin like bet365 .