When buying other items, do you expect to pay less when you pay in cash? After all, the retailer is making more money by avoiding credit card handling fees.
Many merchants offer a discount for paying in cash or charge a fee for using a credit card for small purchases. The only reason such practices are not ubiquitous is that they violate the merchant agreement.
Many do, yes. For those that don't – the majority – I'm curious if pessimism finds their actions as distasteful as he found Flexibits', the authors of Fantastical.
Personally, I find nothing wrong with their actions. pessimism was never purposefully mislead about how Fantastical was being sold, and it's perfectly reasonable for Flexibits to charge the same price in both venues even though they have larger margins in one.