Those you mention use USD. On others it can be different. It is geared towards their target market and regulations. The French based site Winamax uses Euro as does any of those Ipoker skins like
william hill and Befair which are UK based. You can still deposit with US but either they or your payment processor charge a very small currency conversion fee.
On Pokerstars there used to be Pounds and Euro only buy in tourneys not so long ago. I don't see them anymore now everything is US and they convert your local currency if it is not USD.
I haven't found a poker room or casino that shows my balance in my local currency. Only a couple bitcoin wallets.