This is a good verse to remind us to be grateful for what we have because of hard work and God's blessing. We can go to bed at night with a grateful heart without regret. We earned what we have because of our labor and we're also aware that much of what is in our possession is there because God gave it to us. What a quiet and glad spirit we can have with that.
But, for those who achieve their wealth through underhanded means, who get what they have by cheating others out of their wealth, or who just outright rob people, these will always be looking over their shoulders. They'll either have regret when they seek to sleep, or God will fill their hearts with guilt and shame because of the ill-gotten gains. All their "wealth" will never be a good substitute for inner peace and joy that the righteous can have.
Hard work may not achieve great monetary wealth, but it will achieve something far more valuable: peace knowing that your heart is right with God and with the people in your life.