Reputational problem not a technical one. People who join the network only with the expectation to earn money can be disappointed from the low farming rewards and this can motivate them to start competing networks or simply to spread bad mouth. More people joining only to farm makes it worse.
I dont see it a problem later when the network is big, but I can imagine this being a thing at the begining when people dont know what to expect and are full of expectations. Maybe I am overthinking.