There's something about farts. Have you noticed that the farter never really seems to notice their own stink? I'll be honest, I'll put it out there (so to speak) - I don't mind the smell of my own farts. I'm not saying it's enjoyable, nay, nay. But there's something very comforting about knowing exactly where that smell is coming from. I made that. (Prideful tone not intended, but included nonetheless.) But gas from anyone else's ass, gross. Even if it's the fart of someone you know or care about; if it's someone else, it's offensive.
It's like when little kids poop and want to look in the toilet afterwards. They don't want to take the poop home and snuggle it, but they do want to see what they made. Did I say little kids? I meant everyone.
So there's that.