Our first time brewing, we feared the foam and rinsed out the carboy with tap water in a moment of panic before transferring the wort. Everything turned out fine but we sure felt like idiots about half an hour later when we looked it up on here. Beer turned out fine and we learned to relax!
More recently, we had some friends over on brew day to show them how the brewing process works. While we were sitting around waiting for the mash to be over my husband was talking about a YouTube video/ad for StarSan he had seen where the inventor or CEO or someone was talking about how it was so safe you can drink it, and proceeded to replicate/test this by taking a full swig of it from the bottle... you can imagine how that one ended, he continued to taste it for the next week! Worst part is, we searched for the video that he was talking about later and never found it.
See a pattern here?