You are seeking a contradiction where there is none. The same people who are concerned about the unequal distribution of wealth, knowledge and power in our economic system are the ones highlighting and protesting the ways in which that economic system is exploiting and harming the environment and impoverished nations.
Maybe, but their concern is more superficial and secondary, while their concern for equality is more urgent. What's more, they fail to realize that they are living better than many people on Earth, and probably even better than they would be living if everyone on Earth got an equal share of the global economic pie.
So what I really think is that people should be looking for ways to sacrifice more for the good of the planet and the future. E.g. someone who drives a car should be taking transit and advocating for others to do the same, rather than advocating more equal pay with others who earn more.
If people really want to argue for income equality, they should be arguing for others to make less. Really it doesn't matter if some people make more or less than others, though, because if everyone consumed and thus spent less, which would be better for planetary sustainability, then they would all be saving more money than they make and that would mean everyone's savings would be growing, albeit at different rates.
They want equal pay for men and women, yes, but limit the obscene enrichment of the 1% - two goals that are easily reconciled in policy. They want poor and working-class people in their country to have access to health care, education and basic material needs while stressing that we should all strive to contribute less to environmental pollution -
The way to limit 'the obscene enrichment' of anyone and everyone is for anyone and everyone to spend less of what they get/have. The more people save, the less they spend, and the less everyone spends, the less revenue businesses make, and the less revenue businesses make, the less money there is to pay out to shareholders, employees, managers, etc.
And the less money gets spent and made in an economy, the less industrial activity and development it can afford; and thus the more resources and land are left to nature.
again, those are things that can largely be reconciled (for random example, cheap yet high-grade public transport available to all, paid by increasing taxes on companies that pay little, would help with both).
Or instead of raising taxes you could just make the costs of public transit cheaper by cutting the wages and other payments made by the companies.
For many of us, the goal is to forge a system that is not inherently exploitative and abusive.
To do that, people have to be liberated from financial dependency. I.e. they need to be out of debt and thus free to choose lower-earning jobs, which they are free to quit because they have money saved up from their low incomes, i.e. because prices are low and they are skilled at foregoing purchases to save money without feeling deprived as a result.
For the incrementalist and reformist among us, eliminating as much of the inequality and injustice within the existing system constitutes small steps on our way to that goal; and even the revolutionary among us have to participate and live in the system as it exists, refusing and protesting its most explicitly injust elements where they can, while they agitate for its eventual overthrow.
Injustice, yes. Inequality, however, is just envy. There will always be people who make more money than others, even people who have the same or similar job functions and skills as you do. Some of them might be your same gender and others the opposite gender. Is gender inequality worse than race inequality or class inequality or aesthetic inequality? Yes, discrimination is terrible but equalization is not the solution. Stopping discrimination is the solution but how do you get people to take the liberty of treating others fairly when there are so many people who simply don't care about anything except having more power to make more money?
Equality politics is too often just another avenue for expressing greed and envy. More important for people to spend and consume less, regardless of how much money they get; than to want more because someone else gets more; and then to feel entitled to spend and consume it instead of saving it because they feel it was harder won as a result of historical inequality.
Honestly, I don't care if women get paid as much or more for men at the same level; because regardless of whether they make the same money or whether one gender makes more than the other; I think they should be saving and conserving resources and acting ethically to achieve sustainability.
The people who should make more are the people who spend less, whether they are male or female. Those who spend more should make less to discipline their spending.