Great question. You are right that, very often and in many places through history, there has been some reluctance to compel persons (through law) to save others when they are in a position to do so. This has included not just a reluctance to compel persons (as in your case) to provide food or other resources to aid others who would otherwise die from starvation, but compelling persons to physically aid others who are in peril (rescuing someone who is drowning, for example). Gradually, in the United Sates and elsewhere, there have emerged Good Samaritan Laws that require (and protect from liability) persons to make *some* effort to assist innocent persons in need (e.g. a passing health professional is expected to assist someone who has had a heart attack when no one else is available, and the professional knows basic means of reviving the victim), but these concern emergency situations. Be that as it may, there have been philosophers who prioritize the right to life over the right to property, opening the door to judging that ownership of the full grain silo may be trumped or over-ridden by an obligation to meet the needs of others, especially when this may done without the grain silo owners suffering (true, if there is a re-distribution of property, the owners will lose wealth, but this need not lead to them becoming dispossessed).
Contemporary philosophers who believe that if the full grain silo owners do not prevent others from dying, thy are gravely wrong include Peter Singer and Peter Unger. John Locke thought that the distribution in a just society needs to insure that (as it were) there should be enough to go around so that no persons are abjectly deprived.