Paypal, Stripe, Square etc all use credit cards which cost 2.x% plus 30 cents. Bitbank uses a digital currency with low or no fees. It's more competing with Visa/Mastercard than with Paypal, Stripe, etc. Those companies could become partners actually if they decided to support it as another payment method.
You know how some people pay with credit card simply to get the airline miles or 1% cash back?
Who pays that? The merchant. (Well, the merchant adds it to the price that everyone pays, but I digress).
Now given the option. Pay $100 with your credit card or pay $98 if paying with bitcoin, which are you going to choose.
Stripe and PayPal both are at 2.99% + $0.30, Square is at a flat 2.75%. So giving the customer the 2% discount for paying with bitcoin still yields the merchant more than had the customer paid with a credit or (signature-based) debit card transaction.
But, almost no one seems to offer a discount for cash - which they pay 0% on and they don't have to wait to collect from the credit card companies.
There are so many of these alternative payments systems available nowadays, but none seem to really offer any benefits (or protection or increased warranties) to me over a credit card to change my personal purchasing behavior.
Merchants incur expenses dealing with cash as well, so accepting $0.98 worth of bitcoin might be equivalent to accepting $1.00 in cash and coin after the hassle of dealing with cash in factored in.
It will be some time before we see bitcoin used at retail, point of sale. But it really solves problems for online purchases -- for the merchant. And maybe that's where the the sweet spot is. If you want what the merchant sells and the merchant wants bitcoin (for the reasons you state -- protection from fraudulent customer chargebacks), you won't be given the opportunity to use your credit card.
