The node is an integral part of the protocols proper as designed functioning. Without the voluntary constructive participation and contribution of enough node operators the protocol could not provision the decentralised, censorship resistant, p2p payments it was designed to enable. If Satoshi was still the sole node operator we would not have a useful protocol. I do not currently operate a node, but can still enjoy the utility of p2p payments due to the generous provision of nodes, by others. You might argue neither democracy nor Bitcoin protocols are altruistic in their outcomes, although they both do seek to treat all participants equally and without fear or favour. But to function both fundamentally require that some 'people work for the benefit of others for nothing in return'...ie that some people act altruistically....by running a node or participating in good faith in the contest of ideas that is core to a functional democracy, or at the very least, voting on the merits of the contestants. In a similar manner node runners can and do choose to adopt and enforce the rules of the protocol, or not, at their own expense. Fiat money in contrast might be compared to a one party state autocracy/kleptocracy...where a small elite enjoy huge privilege and power at the expense of the majority who are forced to participate.