I thought of this question because someone joked about double-dipping their hands in the chocolate fountain at Golden Corral and boy did that invoke one of my least favorite paying-for-college memories.
Yes, someone did dip his hands into the chocolate fountain at the Golden Corral. Worse, he was a repeat offender, a man that was at least in his 30s if not older slurping it off of his fingers and all, sometimes while making eye contact with me or my coworkers. Worse, there was no enforced rule against doing so, at least at my location, so my manager just told me to let him do it, don't make a big deal out of it, and hope he doesn't bother anyone else.
That same manager once insisted on me making the place extra clean a little before Christmas, so they insisted that I use double the amount of cleaning bleach in the same bucket. I explained that's not how cleaning works or how OSHA compliance works. I got a write-up. I said that wasn't an offense that qualified for a write-up, and what they said was "thanks for the tip, I'll find something that is. Your word against mine." 
That same manager punched me out early without telling me, because the place wasn't perfect enough before I left over an hour late, missing my family waiting to pick me up outside by that long to go out to do holiday stuff. I did call that in on the supposedly anonymous tip line later, but you can guess what happens when an anonymous tip about wage theft is called in on a manager that already knows who would call in that tip in a "right to work" situation. 
That same manager was fired a week later for embezzlement, and not the cool kind. They were writing up and firing people for months for money missing from the register. I found out when collecting my last check and noticed someone new. 
I waited tables in my past life. The one experience that sticks out above all the others was a time when I worked for a retired professional sports player. They owned the restraunt and would seldomly host parties in the back room for all of their friends and business associates.
One other server and I were assigned that room one night and since the room was reserved for the owners party, it didn't have any traffic until the party arrived. So we waited for a few hours helping out other servers and generally not making any money. The party arrives and we start busting our tails getting everything for 20+ people. The party eats and then closes the room for the next few hours, not really wanting anything. We get told to stop bothering them so we go back to helping other servers.
The party finally ends and the attendees start leaving. I ask my supervisor about the bill and they say it's been waived by the owner. I ask about the tip and my supervisor just said maybe the guests left it on the tables.
There wasn't a dime on the tables. My coworker and I essentially worked for free for an entire shift and the owner couldn't be bothered to tip their employees. The supervisor could only manage a half hearted shrug.
Makes my skin crawl just thinking about that place.