Catherine Sweeney Hershey was an active philanthropist and inspired her husband to be an active philanthropist himself. His first gift of $5,000 to
Franklin & Marshall College in Lancaster is credited to his wife. When the
Roman Catholic Diocese of Harrisburg was starting construction of the
Cathedral of Saint Patrick in the commonwealth's capital, Catherine Hershey made a sizable donation. The Diocese recognized her contribution by putting the name "Mrs. M.S. Hershey" in an inscription just inside the church's entrance. She is listed in the first two annual reports of Lancaster Charity Society as a member. This society helped the city's poor and needy families. Upon their relocation to the new
Hershey Chocolate factory in Hershey, Pennsylvania, she and her husband worked to found the
Milton Hershey School. She worked closely with
Prudence Copenhaver, wife of the school's first superintendent, where she assisted "in planning the home life program – including menus, clothing, social skills" and more. She signed the Deed of Trust to the school alongside Milton Hershey which suggests she was directly involved as partner in the business, planning, administration, and operation of the school. She was also known for her
landscape and
interior design. ==Illness and death==