That makes sense honestly, B2B SaaS is lucrative, steady, and honestly probably moreso than a B2C business could be. Many of the big software players most people have never heard of.

As a consumer, you're almost certainly in a Salesforce system somewhere, but most people have no idea what Salesforce is.

I wonder what the equivalent is for tech people. What is an enormous industry-specific business we have never heard of?

The steel production and raw materials industry is a whole different world. I am not knowledgable in the area at all but a recent linkedin post by a friend was listing the biggest steel producers by country, I did not recognise any names except Tata from India and Thyssenkrupp from Germany.

Here is a list I found from a quick search, try to guess which country the biggest producers is based in or how many of top 5 you expect to have heard of before opening the link.

https://en.wikipedia.org/wiki/List_of_steel_producers

That is a lot of Chinese steel, at what looks to be about 25% of the total worldwide production, just by the companies listed in the top 41. It looks like possibly a majority of worldwide production isn't in this list (which seems to gut off at less than 10 million tonnes), so it's possible it's even higher, if there's a lot of small steel companies based in China as well.

This is actually pretty amazing. I predicted that the top few would be US based companies but I hadn't heard of them because they are rounding errors. I was wrong about that but the first US based steel company on the list is in my neighborhood. I ride up to their plant on my daily bike ride.

I didn't even know Thyssenkrupp did things other than elevators.

"In February 2020, Thyssenkrup AG's board announced that it would sell its elevator segment to Advent International ... "

https://en.wikipedia.org/wiki/ThyssenKrupp

This just keeps getting more interesting.

Pharmaceutical Distribution - How many people have heard of McKesson?

Oh god. I've worked at a place that uses their apis.

Since this is such a great question, I've posted an "Ask HN" about it: https://news.ycombinator.com/item?id=23534529

I am always amazed when I listen to my rancher buddy talk about cattle prices on weekly calls. There are so many industries I'm completely oblivious to.

Agriculture, including farming (mid sized or larger), fertilizer distribution and manufacturing and seeds.

I actually have agriculture experience. That's how I paid for college. You're absolutely right but I bet there's more than one AWS.

I think many people have heard of John Deere and Monsanto but what about McGregor? They may not be as big as AWS but even with Ag experience I bet there are bigger similar organizations.

I bet there are big custom harvest operations too. We had a two man operation on the Palouse but I heard stories about huge operations out of Texas that migrated through the midwest following harvest cycles.