Voluntary social service is better than money donation. Everyone should do something for society. Physical contribution involves your personal physcial sacrifice and hence very valuable. In North Korea, every citizen does some voluntary work for society after office hours.
Chinmoy- It is difficult to say what is voluntary in North Korea. There the people are extremely brainwashed and so whatever the ruling party and government considers right becomes voluntary.
In totalitarian states subjects are not supposed to have their own independent will and North Korea being one the people are made to obey the diktat of the rulers!
Any progressive and decent society is characterized by the active involvement of its members in areas where governmental efforts fail to reach and we do need such public-spirited organizations and people!