Debit or credit, you are (or rather the shop is) paying the same fees when paying with a MasterCard.
While a Maestro transaction costs like 10 cent, a MasterCard takes X%.
Further the prepaid MasterCard from ICS is like 15€ a year or so, much cheaper than Bunq Premium, and it manages to include the basic insurance, that is buyer protection and 6 month after sale insurance.
My mom had her watch stolen at the gym, she bought it in Malaysia with her creditcard, after the house insurance said they only covered 250€, she called ICS and after sending the form, in 4 days they've payed the whole amount minus 50€ fees.