I am under no illusions that my nice neighbors would share their food stores with me if we were nuked.
I've seen posts on another site that report that mormon "visiting teachers" are making lists of the stores and equipment that members have on hand. Since the vow of consecration taken in mormon temples by "worthy" members states,
One of the covenants we make with the Lord when we receive our temple endowments is to live the law of consecration. The Lord has called this law a celestial law, under which we give our time, talents, and possessions to build the Lord’s kingdom.
• Read Doctrine and Covenants 88:22 and D&C 105:1–5. Why must we understand the law of consecration and be willing to live it?
Concerning this law the Prophet Joseph Smith said, “A religion that does not require the sacrifice of all things never has power sufficient to produce the faith necessary unto life and salvation” (Lectures on Faith [1985], 69).
As the Prophet explained, we must develop the kind of faith that will lead us to eternal life. Such faith comes as we put the things of God’s kingdom first in our lives. "
VOW of consecration in LDS temple ritual. "You and each of you covenant and promise before God, angels, and these witnesses at this altar, that you do accept the Law of Consecration as contained in the Doctrine and Covenants, in that you do consecrate yourselves, your time, talents, and everything with which the Lord has blessed you, or with which he may bless you, to the Church of Jesus Christ of Latter-day Saints, for the building up of the Kingdom of God on the earth and for the establishment of Zion." NOTE: "The Kingdom of God" described here does not refer to the Kingdom of God as most Christians believe, and ZION is described here: "Zion is often used in this way to refer to the Lord's people or to the Church and its stakes (see D&C 82:14). It has also been used to refer to specific geographical locations. "
Embracing the Law of Consecration by Larry Barkdull Link
Has this to say:
We are expressly forbidden to hoard property or claim it as our own: “I command thee that thou shalt not covet thine own property….” Therefore, a Zion person’s claim to his property is subordinate to the Lord’s claim. As Martin Harris learned, property must be consecrated for the building up of the Kingdom of God and the establishment of Zion, which provides that no poor should exist among us. Ultimately we will be held accountable for the discharge of our stewardship.
A Zion person’s stewardship, sometimes referred to as “portion,” or “inheritance,” is to be used to support his own family, and then “conveying back to the Lord’s storehouse any surplus which accrued [for the poor].
Substitute The "The LDS church for "The Lord's, and "Bishop's Storehouse" for "The Lord's Storehouse".
I do not recall every being taught that the storage that members kept was to be shared with "gentile" neighbors.