Thanks for the info, two questions:
At the QR transit counter (after clearing security transit check) is it possible to pay the fee by credit card?
Alternatively if I were to just enter Qatar without entering transit area and then take uber to the souq and do the shopping/dining there, is it possible to go cashless and just depend on credit card?
The transit counter did take credit cards, though I recommend booking online as tours do supposedly sell out (though probably less so now that there's a cost associated with them). I'm not sure if it's possible to independently do everything (taxi, shopping, dining, etc.) cashless, so I'll let someone else answer that.