Monster blobs lurk in the sewers beneath us, silently growing until the wreak havoc on the civilized world. These are fatbergs, masses of congealed fats, oils, and grease (known as FOG) entertwined with solid debris that shouldn't be in the sewer to begin with. When fatbergs grow large enough -and some have been over 100 tons- they can bring an entire municipal sewer system to a halt. But exactly what goes into a fatberg varies from city to city.
But beyond that, you have to think about the people who find, retrieve, and study these fatbergs. It's a case of "someone's gotta do it, just glad it's not me." Read about the study of fatbergs and what they've discovered so far, at Atlas Obscura. Meanwhile, remember that saving room in a landfill is not worth destroying a sewer system.
(Image credit: Stephanie Birdsong)
In my working life, I had to deal with these things and did so via the Muffin Monster - https://www.nomorewipes.com/choose-your-grinder/