"A matter of ethics," is pretty strong stuff, Aaron.
By your own figures, you're talking about an increase due to fabric weight of 2-3 oz, or 6-9%. People who make their own gear (as I do) would say that's not far out of line from expected variation between one lot of fabric and another. And in this case, the (very slightly) increased weight translates to increased performance.
I have no relationship with TarpTent (don't even own one) but it seems they are the best known of the cottage products outside our little gram-counting community. I suspect most of Henry's customers care more about a tent that doesn't leak (or "mist") with stakes that hold, than minor variations from published weight. Me, I take *all* manufacturer's specs as estimates--+/- 10% is no big deal.
You ask if 9% increase for everything in my pack would make a difference? These days, my three-season BW is about 7#. So no, a 9% increase wouldn't really be noticeable, except on my spreadsheet. In fact, I recently increased my pad weight by about 45%, for the increased performance of a better night's sleep.
Your choice of shelter and the sleep systems and backpacks you've considered on other threads make it clear weight isn't your top priority. If you wanted it, a different shelter could easily save a pound vs. the Stratospire.