The price of gas primarily affect the poor way more than the rich. They both pay the same but while one is paying 15% of their wages for petrol, the other is paying <1%. Simultaneously, the poor are being pushed further from the urban core, and jobs, and are spending more, in time and money, to get to those jobs.
That's the point. It forces the poors to live like "good poors" in an urban apartment and ride the bus rather than living on the outskirts and driving a shitbox. Of course the people that promote these policies have a less blunt way of putting it but that's basically the incentive they're going for.
