What could explain the mechanics of how this happens?
Surely FB employees aren't managing those bot accounts themselves. Do they generally determine accounts that engage with ads to be "human/real", thereby incentivizing bad actors who spin up fake FB accounts to click/"like" ads?
They could also do it at arm's length. A lot of MTurk-style sites have loads of jobs along the lines of, "click this ad, fill out this form, get $0.02".
Surely FB employees aren't managing those bot accounts themselves. Do they generally determine accounts that engage with ads to be "human/real", thereby incentivizing bad actors who spin up fake FB accounts to click/"like" ads?