Manna has become the symbol of God’s miraculous provision to the Israelites, and generally.
In Deuteronomy, Moses explained the reason for manna:
8:3 Yes, God humbled you by letting you go hungry and then feeding you with manna, a food previously unknown to you and your ancestors. He did it to teach you that people do not live by bread alone; rather, we live by every word that comes from the mouth of the Lord.
This was referred to by Jesus several times. When Satan tempted him to gratify his hunger pangs by turning stones into bread, Jesus’ answer was:
Matthew 4:1-4 People do not live by bread alone, but by every word that comes from the mouth of God.
When the people misquoted their own scriptures (saying Moses provided the manna) to ask for a miraculous sign so they could believe in Jesus:
John 6:30-36 Jesus said, “I tell you the truth, Moses didn’t give you bread from heaven. My Father did. And now he offers you the true bread from heaven. The true bread of God is the one who comes down from heaven and gives life to the world.
In that light, the Israelites’ complaints were not a good look: