They aren't necessarily using perl, you can set your webserver to parse any file extension using whatever (perl, php, etc).
On my server I setup .html files to be parsed as .php files. All I added was a line to an .htaccess file.
As for Cold Fusion, I looked into it several years ago and gave it the big thumbs down. For starters it generally runs on Windoze web servers. That alone is enough for me. But I also noticed that busy sites running CF were always painfully slow, and suffered a lot of downtime.
I'm hoping it will just slowly go away
I'm the Dude. So that's what you call me.
That, or Duder, His Dudeness, Or El Duderino.
If, you know, you're not into the whole brevity thing