This comes up every time someone suggests pricing a scarce good (either with Pigovian taxes or privatizing a scarce resource), but it has an easy solution: [p]rebate everyone the amount of tax they would pay for poverty level consumption of the resource. That preserves all of the incentives to cut back on a marginal unit, without penalizing someone for being poor.

Facing economic realities doesn't mean keeping staying with systems that rewards the wrong thing.