It's not like they spam/share their faucet rotators outside Micro-Earnings section.
IMHO, referral links (if allowed) would be mostly shared in the micro earnings section too, as well as signatures; but faucet rotator owners put their links in their signatures as well so it's pretty much the same there.
Make a faucet rotators needs time and money, so just let them earn small amount of money.
Wrong and wrong. There are a lot of faucet rotator scripts out there that someone who doesn't know how to code to save their life can use to make a rotator. Also, money? Where does money come into play? Domains aren't required (or sometimes they use a domain they got for free, like the .XYZ giveaways), and there are always free hosters out there.
Most people know that faucet is just waste of time anyway
The hundreds of people who regularly visit Micro Earnings prove your point wrong.