Concerning payment being contactless and Avion only, it reminded me of when DY started their long haul venture. On board paiement were cards only. During the first month after the launch, an old women has to be taken away by paramedics after landing : dehydration. She did not have a valid credit card (only some local debit card) but enough cash to buy water which she asked for.
I do not remember the follow up but now either water is free or cash accepted on DY.