Although there are few exception such as Bitcoin where people usually run full node to perform community service or help Bitcoin network, it's not reliable option unless your coin is very popular.
Running a Bitcoin node doesn't help only the network. It helps you turning your wealth private. Back in 2009, it may was pretty much like the case with this project, but now that it's being taken seriously, running a node can actually be very profitable for you, whether someone pays you for doin' it or not.
While i understand your point, privacy isn't financial reward and thus most people still won't be interested.