Yeah I have seen too many times some businesses and restaurants go through the motions of what has been handed down to them, without really understanding just what they are doing. NaOH isn't THAT toxic, the real hazard is when it gets wet. Especially in your lungs, eye, mucous glands, etc. Sodium Hydroxide is a strong base and when it's dissolved in water, it feels like a soapy solution. You can rinse it off your skin and it takes a lot of water and rinsing to feel like it's fully neutralized. It's probably up on the hazard list with pool acid. It will dissolve your skin if given enough time, but it's also harder to rinse off.
In regard to Lye, also from Wikipedia --> "Lye is used to cure many types of food, such as lutefisk, green olives, canned mandarin oranges, hominy, lye rolls, century eggs, pretzels, zongzi (Chinese glutinous rice dumplings), and Chinese noodles. In the United States, food-grade lye must meet the requirements outlined in the Food Chemicals Codex (FCC), as prescribed by the U.S. Food and Drug Administration (FDA). Lower grades of lye are commonly used as drain openers and oven cleaners and should not be used for food preparation. Lye is a strong alkali, producing solutions of about pH 13.0."
Historically lye was potassium hydroxide (KOH) and the term "lye" is considered a "common chemical name" referring to a strong corrosive alkali. In other words "lye" is not a descriptive chemical name. It would be the equivalent of using the term "Dog" instead of german shepard, collie, bassett hound, etc. Anyway lye was traditionally made from potash and used to make soaps and bleaching compounds in antiquity. I think the reason they ban the use of this stuff primarily in food production is because it's better to use the actual chemical name, such as sodium hydroxide or potassium hydroxide. If you say "lye" it could mean either. Also in todays world, "Lye" is used as a drain cleaner and the purity is not food grade. When you consider the usage of the word "Lye", there is confusion on what it actually is you're using, plus there is a stigma attached to it that it's a lower purity chemical (drain cleaner).
One comment you made raised a big red flag with me. You mentioned it looks like pretzel salt. If you think this, so might others. PLEASE PLEASE PLEASE make sure you store it in an airtight container that is properly labeled! Personally, I store mine in a properly labeled container "CAUTION NaOH, DO NOT GET WET" also NOT in the kitchen. Reason being is if someone does mistake it for salt, they will be cooking a toxic meal and ingest it. You are now aware of the hazards, but its the friends and family that come over to cook and mistake it for salt that may be unsuspecting. Make sure people in your house know what it is.
If you read that other thread you'll see that the NaOH ruined my cookie sheets. What I do now is I use baking parchment. I make up the sodium hydroxide solution then I have a big bent flat spoon with holes in it. I put my pretzel on the spoon, give it a dip, raise it to drain the excess, then slide it off on to the paper. This has worked really well for me. You could probably also use a big wide slotted spatula. As for disposal, it's all about diluting it with lots of water. Remember to do it slowly, adding more and more water, then dump the bowl and run the water in the house a bit. I haven't had any issues with my plumbing but then again it isn't metal. Good luck and post pics when you make em!