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You still have to put the pearl on to do anything with it. I mean cmon, no one is going to forget you did something really stupid, so dodging by not equipping the pearl only means you're not...

1) if bad people join your linkshell, you can break their pearls. Simple. How you can't do this before they "wreck things" or "make you lose frends" is beyond me.
2) Unless you're promoting these...

There's going to be bad apples in every game. If it's a concern you don't use the NPC. Fortunately from what i've seen this is really the exception not the rule.

The whole point of the concierge system is for linkshells that are just accepting general members. If you have coniditions or need to approve people, well, I'd say the system wasn't designed for you.