[brndnmtthws]

Not necessarily. There are also some coins which use methods of securing the network which don't require incentives (ex: RaiBlocks).

[SimbaOnSteroids]

Then how does RaiBlocks plan on paying the bills of running a node.

[Donzo]

The proposition is that free, instant transfers are so awesome that people will voluntarily run nodes.

I like Raiblocks. It really functions the way that people want Bitcoin to function (free, instant, complete [no dust] transfers).

[brndnmtthws]

I suggest you read the white paper if you're interested: https://raiblocks.net/media/RaiBlocks_Whitepaper__English.pd...