Stomach contents have been used for years in forensic determination of the deceased's recent history. That's not too far up the "canal" from feces.
If you want feces stories, I could tell a few. I've spent the past 42 years watching and working in other people's poop. In my younger days, it was nothing unusual to be standing in raw sewage watching the undigested corn and lettuce running between your legs. Of course, in that same stream are "whte mice" (used tampons), used condoms, tampon inserters, and lots of "chunkey chocolates". When putting new wastewater treatment plants on line, I like to invite local 5th - 8th graders to take a tour. When they see the raw sewage coming in a headworks and the clean water leaving the facility, it's an excellent educational experience. As a society, we've become "soft" and take so much for granted. When we turn on a faucet, we assume clean drinking water will "magically" appear. And, when we flush the toilet, those things we don't like to discuss magically disappear. Most don't give a second thought to what happens between those two points.