It's not "farming", they're just directing their votes to something other than content at this point in time, before that it used to autovote users for example.

whatever deal they may have between each other is among each other in terms of delegations/payments, point is it is not abusing the curation rewards pool by earning author rewards as well as curation rewards.

Maybe just jump on your main account next time and ask rather than hiding behind a brand new alt account.