If you have your own server then of course you can do fancy deployments, but locked down shared hosts make it harder. Ftp is lowest common denominator to get your stuff up. I'm just saying that many people need to work in these environments and don't have the luxury of being able to deploy in cute ways.

Also I find developing wordpress/drupal sites that working directly on the dev server is fine, and committing from there is the best flow. It can be a big pita and time waster trying to maintain these sites in different places just for shits and giggles.

moondev assumes that someone who uses a VPS is more likely to use SSH/version control rather than FTP.