Category names in url’s don’t matter

I use category names in my urls, and the format is as follows:

https://www.nomeatathlete.com/category/title

I decided to change my category names, and I’ve been setting up 301 redirects so as to avoid having duplicate content hurt my search engine rank.

In the process, however, I discovered that when I type anything at all into the “category” slot in the url, the pages still load just fine. The category slot doesn’t matter at all! Can anyone tell me what is going on?

This doesn’t really cause me any problems, but I try to make my blog as visible to search engines as possible and I’m worried that this might a symptom of some big issue.