Though not everyone is aware of NPC scan, I know a few people with rares who do not use it. I personally don't, I use the overlays from it but I use SilverDragon otherwise. I've never had issues with people having tamed rares near me due to this.
But you can't expect someone to go through all that effort to tame a rare and not use it out in the world. I try to make an active effort not to have a rare out in the zone it's from (Though a different rare not from that zone....is totally fine. If you really freak out because Loque is in Twilight Highlands...you have issues. I'm going to farm my leather and level my pets somewhere.) Because I know about NPC scan and I know how frustrating it can be when people have the zones rare out and about...particularly if they named it after the tame.
Getting mad at someone because they were running around a main city with their rare pet out....is just silly. We don't tame them to have them sit in a stable forever. That would be just pointless, so I would hope people don't get mad at people for that.
As to the flaggers with rares named after the rare...or the shadowmelded night elf with the rare out in its zone..at the spawn point. Well....they need to find something better to do with their time
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