My plumber always tells me never to use drain cleaners, so I wouldn’t say nobody worries about it...

Your plumber tells you to never use something that might result in you not needing his services? Imagine that!

Devil's advocate: the back of those drain cleaner solutions make a point that the solution should never sit or pool in any surface or pipe. You have to run water and chase it down so it doesn't corrode the pipes. I know where I live some of the pipes have "flow issues" because of bad design, and if there was already a partial blockage I can see drain cleaner corroding the pipes...

We just mechanically clean them out ourselves, anyway.

Maybe if you have metal drain pipes. They sell the stuff in plastic bottles. If you have PVC drain pipes, it isn't going to disolve them.

If you ask them why they say its because it'll often dissolve the pipes before the blockage. Most of the trades people I talk to aren't looking to maximize their work. I've had them turn down jobs for being too gross and I don't blame them.

They'll generally use a snake/auger. Home Depot sells a basic one for $15. The beefier, further reaching ones cost more. Or, for smaller jobs, there are single-use plastic snakes.

You should avoid drain cleaners because in high concentrations they corrode metal.

The compound is fine in your dishwasher because it will fully react and neutralize in your plastic or coated metal dishwasher casing.

But u happily eat it on pretzels? There's no issue in low concentrations

People most certainly don't eat sodium hydroxide on their pretzels anymore than they eat raw egg in their cakes. Coating pretzels with lye before baking causes a chemical reaction that consumes the lye. You really, really shouldn't ingest any amount of lye, lest it react with the inside of your squishy organic matter like the surface of pretzel dough...

Sodium hydroxide (NaOH) is lye, which shouldn't be consumed. Pretzel salt is sodium chloride (NaCL).

In German, I think their full name is Laugenbrezel. The full name may not be much used[1] colloquially, because it's implied -- but bread rolls made the same way are definitely called Laugenbrötchen.

"Lauge" is German for "lye". They're called that because they're made with it.

[1]: Though when I switched my phone keyboard to German just now to test it out, the predictive spelling corrector suggested "Laugenbrezel", not "-brötchen", when I'd got as far as "Laugenb".

Nope, pretzels are made with lye (NaOH). That's how you get the tasty brown Maillard reaction coating - boil the dough in lye water, then bake, then salt it.

Though it doesn't have to be lye - you can use other less caustic bases, such as baking soda.

Some traditional pretzel/bagel recipes use lye: https://www.bakespace.com/recipes/detail/Soft-Pretzels-using...

Lye is used in the creation of pretzels and bagels.