It sounds like the general point here is that priority is always given to those who are going to be using a base for active purposes, printing/nuking, etc.
Shop owners are allowed to, and generally should, use a building for a shop. But it is not a requirement. Also, shop owning on its own counts as a passive activity, as a shop is not a raidable entity, and RP houses in general are meant to constitute a passive activity.
I'm not advocating for Jack's ability to do this, but we all know that the elevator base in S1 is one of the most popular places to base. Though, it's probably more commonly used for nuking than printing. Thus, it's a generally prized location.
Could he have reached out to the other members of the base? Sure. But it might also be prudent in future to co-own the door. Otherwise, you're more or less just putting your shop in some AFK dude's place. It's not really conducive to an amicable outcome. And the others were right - it's not Jack's responsibility to check in on everyone inside the base unless they specifically have a stake there - I.E. They co-own the doors.
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