Why aren't previous license codes saved in my account?

I have purchased Turbotax every year for at least 10 years.  Most of the time, I buy the CD version and then go online to my Intuit account and enter the license code so that I can download and install it.  I was under the impression that these license codes would be saved to my account.  I see the previous versions under my history when I go to purchases and downloads.  However, when I go to download a previous year, it's asking for the license code again.  So Intuit expects me to save the license codes somewhere else (keep the cases, save the codes on my laptop, etc) instead of saving them for me?

 

I don't understand why the codes that I pay for and then enter online are not saved to my account.  That's how it works for most other software licenses.  I can go to my Microsoft account and see every license I've ever purchased, whether the code was purchased was digital or physical.