While I know that WinRAR has some die-hard user bases, I have never been sure who their paying user base is. Are there some companies that are completely dependent on WinRAR for some internal processes?
I'm one of their paying user base. To me WinRAR is like the VLC of archives. I can throw almost anything at it and it will work. Other compression tools, not so much. I'm also a fan of giving money to small, independent developers.
I remember RAR being popular in the early 00's but when 7-zip started becoming a thing I switched to that, and then I rarely saw .RAR's.
RAR seemed to handle large collections of files better on Windows than .zip back in the day, and it had a few features that .zip didn't, so it was something I typically installed on like Windows XP and such back then. But I'm not sure why anyone would use it over 7-zip today unless you have massive numbers of old .RAR files laying around.
I did work for a company that actually licensed WinZip because it was easier to use than the default Windows interface for .zip files.