I think where people are getting weirded out is the feeling that people need to protect OP's girlfriend. There feels like two scenarios:
* OP is telling truth, girlfriend consented to upload. All is fine.
* OP is lying, girlfriend has no idea. OP has breached trust of his girlfriend. Their relationship is worse off for it. OP is a dick. OP's girlfriend is none the wiser and goes on with her life none the wiser.
It's coming across as people just wanting more proof because they are skeptical, and saying "BUT THINK OF THE OP'S GIRLFRIEND!" to justify their own skepticism. Not saying that's what it is, just saying what it looks like.
No proof is ever enough for GAF.
I think the issue here is that this wasn't really a thread that required "proof."
I mean, requiring proof in threads tends to make sense when the OP is making some incredibly lofty, dubious, and potentially inflammatory claim, in which case the mods step in and ask for verification. This is why this tends to happen more on Gaming Side than in OT.
But this thread topic is incredibly basic. Just "My Girlfriend Says/Does Something During Sex That Weirds Me Out". That's a pretty common situation that plenty of people find themselves in. So common that proof is really unnecessary; you either believe the premise or don't.
I mean, if it hadn't been "Thank You," if it had instead been "My girlfriend likes to tickle the skin around my butthole when we fuck, I'm uncomfortable" would people have been clamoring for proof? Most likely not. Most people would have just taken him for his word or ignored the thread.
So, in this case, the clamoring for proof just came across as HornyGAF's thinly veiled desires to hear OP's girlfriend make sex noises.