Koreans have a strong collection of symbols for luck, and for different KINDS of luck.
Amongst their more popular symbols is the one for Wealth, as most people have a desire and need for increasing their wealth, as it directly increases their quality on life, or at least that is what they think.
There is the luck that comes from being at the right place at the right time, and there is the kind of luck that comes from doing your best, working hard, and on focusing on reaching your goals. Someone who attains the luck of abundant wealth typically needs to have BOTH kinds of luck concurrently. That is what they mean with the lucky symbol for wealth.