These were fairly interesting reads. I get that if twi people know each other and are exchanging merit it's not as unacceptable if they know the person is going to be a good poster. If I had a friend who signed up here and has posted well for a few months and is making good quality post, I'd give them merit to rank up for their next rank and I believe that'd be fair.
The idea of merit is rewarding good posts, simple. If a friend make a good post then other one can give him/her merit but what actually happening is (in most cases), all these so called friend groups as simply exchanging merits in between each others. The posts are awarding merits in between friends (in most case again) are usual lazy posts.
However, no one you have accused here has explicitly denied doing it so stick to what you're doing OP.
-I am trying my best to be biased with anything when I tag the merit abusers.
There isn't really any rule against it per se and it's not really enforced at an admin or staff level, so it's more of a community issue right now much like scams and other such shady behaviour. As far as I'm aware the only thing that is currently prohibited is merit sources selling their merit though I'm not sure what the punishment for that would be other than them being removed as merit source.
-I need more information on this.
I am trying to get it from hilariousetc