I can see where you're coming from here. I think this is a matter of standards vs. best practices. The Tribunal (and community!) really should only be rejecting niches based on the criteria set by the system: unique, no profanity, no misspellings, English, and complies with the TOS. I don't see imperfection (or lack of perfect consistency) as a standard that must be upheld. There is gray area and margin for error. Some niche descriptions are sub-optimal and may not follow best practices, but that doesn't mean the niche should be rejected. I would agree that mentioning exclusively "online" shopping isn't ideal for a general "Shopping" niche, but I also see it as a very minor issue that isn't sufficient grounds for rejection. I think people will easily understand the "Shopping" niche by the name alone.
Now, if we're talking about a Politics niche that exclusively mentions sports (as one absurd example), we'd have a stronger argument for rejection.
Ultimately, I don't see this as a contradiction. Molly's post simply refers to best practices when creating a niche to ensure optimal efficiency for a niche's success. Not abiding by those best practices won't be grounds for a rejection, however.
Does this help explain the reasoning? As always, we appreciate your level of engagement and thoughtfulness!