So far merit is a great idea to reduce the number of spammers and quite efficiently despite the many pros and cons.
but the power still often finds the number of people who created cloned accounts to get plenty of places in an airdrop or bounty program
It can reduce the number of spammers in these ways:
1) Staff can observe suspicious behavior of members giving merits to their alts. Those accounts can be banned or given negative trust.
2) Spammers will realize that there is no point in shit posting as no one will give merits. So they will leave.
3) Instead of operating multiple accounts, members will focus on one to rank up easily. Getting merits in multiple accounts is also hard.