The bottom line for me is that if we are to advance into the old 'East' then it is clearly nonsense to suggest we pay the same salaries as someone based in London or Paris.
You are correct in assuming that paying the same is nonsense in these locations. I'd be more inclined to include an extra 'incentive' package for 'hardship'. Other than that, different pay for the same job is a pandora's box...not to be opened until the oil runs out