Tbh I think it's weird when remote employees demand hq market rates. Where it the incentive for the company? You can hire talent from anywhere? Many of the best people are not willing to work from home, it's not for everyone, so I don't believe it's such a huge plus. Also why should you earn twice as much as your neighbour who is equally qualified and brings the same value to his/her employer? You will also have much more disposable income that onsite workers. All of that doesn't seem fair.
If this was the case shouldn't big tech companies pay the same salaries globally for onsite workers as well? They don't, not even close.