If you're looking at the marketplace descriptions, then it means "you must arrange payment with the vendor of the plugin" (The other option is that you pay Atlassian as part of the package and they deal with the vendor for you).
If you have a licence for the plugin, your organisation would have acquired it from the vendor and that should be recorded somewhere. If you're really not sure, then you might want to contact Bob's organisation directly to see if you have (I've inherited a Jira where admins have left no list of what they've bought for me to refer to, let alone the rest of the config they'd done - that was... fun...)
No, that's the point - the phrase simply means "you need to pay for this via the vendor"
The website has no way of knowing if you've paid for it already.
If it were "paid via Atlassian", it would show in your Atlassian account on myatlassian.com but this is third-party.
Hi all! My name is Miles and I work on the Marketplace team. We’re looking for better ways to recommend and suggest apps that are truly crowd favorites, so of course we wanted to poll the Community. ...
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