In my entire career I've never used it - does anyone still use CGI scripts on a day to day basis? If so, what for?
It might not be sexy, but it is easy to test, and allows me to use a wide array of Perl modules in my codebase.
We used to use them for formmail scripts and collecting email addresses for mailing lists on otherwise static websites. Once I convinced that employer to move our clients to hosting that supported PHP (yes, PHP - this was 2006-2007 after all), and to gradually migrate them onto content management systems, CGI became unnecessary.