Do they not know that Allah expands sustenance to whom He wishes, and He limits it to whom He wishes? Indeed in that there are signs for the believing people.
As explained in verse 6: 165, the purpose of deputing mankind to the earth is to test each individual with whatever they are provided, such as health, wealth, children, influence, etc. Food and sustenance given in limited or abundant measures are also a part of this Trial. But only one in a thousand believers, who utilizes Adhikr as the Balance and Trust to keep the universe in equilibrium, will admit this fact. Such a believer tries to utilize all the favors given to him under the Light of Adhikr, thereby earning Paradise for the Hereafter. See explanation 2: 62; 34: 34-39; 43: 32-35.