We have been warned by God's former and current prophets that many terrible things are headed our way. If we have faith, we will trust God, and we will seek him to find out what we should do to prepare ourselves temporally for what is coming. This preparations will extend beyond the needs of ourselves to those who will survive but will not have the means to prepare or to bring their preparations with them.
Some people suppose that God will miraculously intervene for the righteous, and therefore they need not preoccupy themselves with preparation. How can you ask God to care for you when you find yourself in need if you had the means to prepare, his word on what was coming, and still did nothing?
God says "if ye are prepared ye shall not fear." (D&C 38:30) Truly, the greatest preparation is to have a real relationship with God and to be prepared and willing to yield yourself fully to God's will. Although temporal preparations may lengthen the life of the wicked, full yielding to God is a necessary condition to survive the full extent what is coming. But is it a sufficient condition?
Noah's faith and integrity was not sufficient to bring him through the flood. Nephi's righteousness was not sufficient for God to feed him miraculously (1 Nephi 16). The brother of Jared was able to pierce the veil through his faith, but still had to bring supplies of all sorts on his long journey to the promised land (Ether 2).
God granted the Israelites manna in the wilderness, but they were unable to prepare for the surprise journey, and left with only what they could carry. The land they journeyed on was insufficient to support their numbers. Similarly, God fed Elijah during a famine where Elijah had no other recourse.
Those of us in the United States find ourselves gorged on plenty. It is very easy for all of us, yes even those who are poor relative to the wealthy here, to stockpile the necessities of life. It is very easy for all of us, yes even those who struggle to find work, to find employment in areas that are less at risk for the population-driven problems that will shortly be upon us. God expects us to prepare for what is coming. That is why he told us what is coming. Failing to prepare (subject to revelation that might indicate you should not) is a failure to trust what he has said. Those who neglect to heed his words in this regard will find themselves enduring unnecessary death or suffering, or inflicting it upon others by diminishing their supplies through their own neglect.
I know a bunch of people who share my expectation that the tribulations will start relatively soon. Among them, it seems there is a sizable contingent who do not believe they need prepare any temporal thing for what is coming. My advice to them is to seek the Lord on the matter. It could be that they needn't worry about any temporal preparations because they are going to die, or because they are meant to go through a particular type of suffering, or because they are meant to experience a miraculous deliverance, or because they do not currently have sufficient faith to physically move away from the suburbs and cities to a place where temporal preparations might do some good, or for some other reason. Or, on the other hand, it could be that they are meant to prepare for themselves and for others. If your instructions are not done with an eye single to God, his purpose, and his glory, then I can promise they will be in vain.