The issue with multiple accounts is complex and how they attend to it depends on the reason for the other account(s), how well-established you are on the forum and how you get to use the accounts. It's no news that there are some people on the forum who own their alt accounts and people know them but they do not care about it because they are established well enough, this is even as they join campaigns with it.
Also, the forum encourages people who do not want to express themselves with their main account to open another one to do so without issues. But there is nothing you can explain to some people, once you are not well-established, they would tag the account to render them useless on noticing they are alts if they couldn't get them banned for some reason. So this thing is partial and I urge them to often cool down.
But I don't know what anyone would be doing with three accounts, that's where it gets most ugly.
You account can only get tag if you are using them to farm either merits or to farm a campaign. Let say if a manager launches a campaign and put rules that no multiple accounts is allowed to enroll in their campaign and you happened to do so, all they will do is to get them tagged and rendered the account useless because you didn't abide to instructions.
Another thing again is do not share the same address with others like using one general wallet to be apply campaign this shows that you are obeying the rules and can easily gets tagged, the issues is how to manage all those accounts if you don't wanna get tagged, however no established members will attack you if you follow the rules correctly.