Why is this?
Because many people do NOT like hand-coding and don't mind generated garbage, so long as it's either valid-enough for them or whatever.
Also, the tools you listed often have other features some find useful, so they may well hand-code but use stuff like code-completion, ftp (gawd dreambeaver's ftp is known for security holes, unless those have been fixed recently), code folding, whatever.
I would think that surely Dreamweaver beats the competition when it comes to FTP and file handling stuff.
Try sshfs. It's teh jawsome!
Some people may be used to working in an IDE for other stuff and so keep using it for simpler text editing as well.
Beyond that, there's no real special reason people like those tools. Tools is tools.