What is the ruling on wearing the niqab for shopping with the aim of avoiding exploitation by merchants regarding prices?

It is permissible for a woman to wear the niqab for this purpose, and it is permissible in all circumstances. She should be advised to wear it seeking closeness to Allah and desiring chastity, and as a prevention of causes of temptation. By wearing it for the sake of Allah's pleasure, she will attain the good of this world and the Hereafter. Covering the face is obligatory, especially in times of temptation.