“And behold, it is wisdom in God that we should obtain these records, that we may preserve unto our children the language of our fathers;”
Knowledge, written communication and education brings commerce, prosperity and wealth. The Lord wants to bless His people with wealth, as can be seen by so many good church members being financially well off. In order to do that we need to have the means to be educated, especially in the commandments of the Lord. This is perhaps one of the less-thought-of reasons they went back to get the brass plates.