With the nonstop stream of dreck that is legacy broadcast TV these days, it is impossible to know or have seen everything, but some of the big stuff that people eat up that I can't fathom includes:
Any show with "Real" or "Housewives" in the title
Any show with "Ghost" or "Paranormal" in the title (I do make an exception for "Ghost Adventures" as I can still laugh at their brouchieness - that's a word I made up to describe bro-culture douches, feel free to use that but give proper credit.)
Shows about inane jobs, i.e. Ice Road Truckers, Deadliest Catch, Most Unhygienic Stripper Poles, etc...
I don't believe in guilty pleasures, you enjoy whatever you choose with no shame, and I count these among my favorites:
Botched - the plastic surgery guys from Beverly Hills. (Blurred boobs are better than no boobs at all)
Dr Pimple Popper - having seen more than my share of videos like this on YouTube and experienced it in real life, it's nice to see a professional at work.
Sister Wives - can't really explain why I like this show, I'm against religion/marriage in general but I eat this up. My wife does, too. BTW
Does the original or the reboots of In Search Of... count?