Many airlines did away with the freebie for debit card. Others did not charge a 'credit card' charge, but a booking fee. Nearly all my concerts are by on-line agencies and they charge a booking fee. I've alway wondered why. I'm doing most of the work and the computer e-mails my ticket. It's fully automated with me doing the manual bit. OK they have to design the website in the first place, but how much is that?
It was coincidental at XYZ LoCo a few years go. They charged €6/pax for booking (even though the credit card companies said it cost 30c). They carried 65m pax and the profit was +/-€400m. i.e. the credit card charge = annual profit. Curious that. Then they added the EU compensation surcharge for e.g. volcanic activity at €2/pax. 85m pax = a nice boost to profits and their payout has been peanuts. i.e. the credit card charge is too important a profit generator not to be recovered elsewhere. there will be ways.
All these companies have you but he short & curlies. You can only book via internet & credit card and they have free reign how much they charge for that facility. It has always been daft in a supposed transparent consumer market.