As others have pointed out, it's not true for some industries: auto repair, enterprise software and college tuition. Also, cell phone and Internet service "bundles".

All of these industries have at least one thing in common: they're kind of scammy.

Sure it is. Auto shops have a labor rate. Say, $150/hr. That's the price. For parts, you'll pay the same markup as the next guy. You can negotiate, but you can negotiate ANYTHING.

They also have a big book of how long each individual repair should take.

If your insurance company has preferred repair shops, do you think the insurance company is paying the standard rate? They do have a better negotiating position than you do.

Of course, this isn't as big of a problem as it used to be, back when they didn't post an hourly rate.

College tuition (at least, my state college) is straightforward. They even gave me an extremely detailed breakdown of every single fee that was a part of my tuition.

I was about to say, college tuition is pretty clear cut. At least in the early 2000s, what they mention on the website and the estimated books/equipment costs pretty much lined up with what I saw on each bill. Some people paid less because of grants (although some people did have their grants disappear when FAFSA decided to change the income brackets), and I guess some people didn't look at the cost, but instead at their student loan returns.

But I was an engineer. I'm sure there are other fields that might have crazy hidden lab costs.

Some people have grants or scholarships, some get free tuition, mostly at the discretion of someone in the administration. And some of us worked our way through grad school, paying MSRP.

I guess that excludes enterprise software companies.

college tuition

I would wager it is not true for any business.