Someone who has disposable income but doesn't care would buy normal eggs before, lowering the demand for regulation-compliant eggs.
Now, the store only stocks regulation compliant eggs, so that's what the person buys, increasing demand.
Someone who has disposable income but doesn't care would buy normal eggs before, lowering the demand for regulation-compliant eggs.
Now, the store only stocks regulation compliant eggs, so that's what the person buys, increasing demand.