At $10/yr per domain, I just don’t get it.

What am I missing here???

I am still getting up to speed with all things domains, having stepped away from it in the 90′s.

I am perplexed why some companies that (would appear) to clearly know the esoterics of typo traffic DO NOT register very well known typo patterns.
There is an example site I came across that gets 8,000+ visits per day, and is specifically in the internet ad business and they have not registered any typo variations on their domain name.
They have a US-regsitered TM. I did not bother to check for other countries.
Even if they would easily win a UDRP claim or if their legal counsel could intimidate a ‘typo squatter’ to give up a typo domain, both of these options cost money- more money than annual registration fees for the typos that get significant traffic.

Is this yet another example of lack of common sense toward computing, or am I missing something obvious?

I have a dozen or so sites that include the word “teachers” and I registered all the same names using “instructors” just to cover all the bases……