I can put a picture of a dime sized group up and claim it was shot a 700 yds on a windy day with garbage ammo. Those postings mean nothing. That is unless shot under supervision of witnesses who will verify that it happened. Group sizes are the inverse of fish sizes.
It's humorous to me that bone Stock Norinco's are reported to shoot MOA groups when the best NM competitors with the best NM rifles can do it on their best days. It's a disservice to anyone reading these posts as they end up expecting the same when 95% of us shooters couldn't do it with iron sights from the bench on bags. You'll never see me post group sizes for that reason.
It baffles me why you think anyone would bother posting pictures of fake groups, particularly when they also post their failed attempts. It's one thing for memories to aggrandize over time, but do you really think people are desperate enough for such meagre bragging rights that they'll actually fabricate photographic evidence of something so irrelevant to real life? I think your extreme skepticism says more about you than it does about anyone else.
Personally, if I wanted to really show off I'd just post pictures of my enormous junk





















































