In classic realms any type of player with 3X networth cannot attack you at all. The large farms are easy to ignore. An empire is a "farm empire" because it has lots of centralization, bureaucracy, forts, depot stations and of course farms. All that baggage drives up networth.
In realm 2 Olsi has 943,000 villagers, 8 provinces, 153 military points and has not made an attack in April. Olsi is a farmer.
Edit: I have played other games where the term "farm" was used for players that are called "gold mines" in Imperia and any players who are inactive enough to be easy targets for resources or points.
He has 1 medal and fought well during first month. After that he developed (for 1 month) and now is ready to fight again. The term "fighter" is not refereed to players who play horribly. If olsi was able to fight during 3/4 of the era (3 months out of 4) it means he is a fighter. If you, as a fighter (in your definition), are able to fight only 1 month, because after that all good players are out of your range, you are not a fighter, but a noob...
Don't confuse definitions without reason. Farmer is the one who plays for networth ranking. Fighter plays for military ranking... That's all. I have never played to win networth race, but this doesn't mean that i don't have a decent networth in the middle of the era.
P.S.
And when olsi spoke about farmers he was refering to players that are used as strategic weapons. It means, players who never fought any battle till the end of the era and stay with their huge army there, just forcing you to use constant army save...