This year I have noticed that more merchants have been encouraging people to use specific forms of payment where they offer customers discount as a result. For example, today I was look at the ToysRUs site where you are immediately plastered with this ad on how you can save 15% on your total order by using Paypal as your form of payment.
I notice that a lot of sites often offer discounts if people use like a Visa too. Things like 15% off your order can add up quite a bit. I guess credit cards like a MasterCard is just too common where my assumption is the merchant rate are either higher or the other companies are trying hard to win more market share during these times where virtually everyone is shopping for gifts.
More reason for you to become responsible in using credit cards as opposed to being scared and defaulting to like cash all the time I say.