This is a statement about stewardship and thrift. You need to compare it to verse 17.
(Proverbs 21:17 KJV) He that loveth pleasure shall be a poor man: he that loveth wine and oil shall not be rich.People who follow God’s pattern for production and consumption have a surplus.
Notice what kind of house has the “desired” (precious NASB) (2530) “treasure” (214). You would expect it to be the house of the rich but it is really the house of the “wise” (2450). You can take this figuratively or literally. Either way it is powerful. Wisdom demonstrates disciplined consumption. Foolishness wastes.
The “foolish” (3684) “spendeth” (swallows NASB) (1104) the bounty that God provides when he should be conserving. It is not how much you make, it’s how much you keep. This could be a statement about our consumer oriented society.
So? Are you a spender or a saver? Do you fix enough for dinner to satisfy or do you throw a lot away? Is your garage full of bounty that you have forgotten about? Use your wealth with wisdom. Start today, not tomorrow. Now, not later.