You have to pay the 3 cent fee, while you dont have to pay anything when paying with a credit card.
So what is really a benefit for using Bitcoins, customer wise?
Some online wallets don't charge you any transaction fees either, so it is entirely possible to avoid the fees altogether.
Some people would rather pay the bank to keep their money safe so they don't have to deal with it, also most people don't like volatility. Maybe in the future the culture of self-responsibility will be stronger, and Bitcoin is a dream come true for those that want to be responsible of their own money (and assume the given volatility of an emerging asset).