The informant’s family and friends trade pennies with every other person at their New Year’s Party and wish them good luck for the New Year.
The informant is from Texas and his family now lives in California every year after the New Year starts they trade pennies with one another.
To me, there are a few things at play with this tradition. The choice of the penny is meant to represent money. Similar to how Professor Thompson mentioned champagne is drank to show wealth and wish for wealth for the new year, and pennies are used to wish the other person financial fortune in the year to come. In addition, this is done to force everyone at the party to wish the other good luck which stops them from carrying any feelings of ill will toward the other into the New Year.