In the face of the epidemic, some people donated masks, and some people drove up the price of masks. Which famous saying is used?

A gentleman makes money in a proper way.

"A gentleman loves money, and takes it wisely" —— Considering that medical materials are in short supply for a time, masks for epidemic prevention have become a hot commodity for a time. However, a few people regard it as a business opportunity, grab sales and raise the price of masks. This is not a blatant attempt to get rich.

Explanation: Gentleman: A talented and virtuous person. A gentleman would rather have wealth obtained by the right way than ill-gotten gains.