Gold standard? Mac apps, when uninstalled naively, leave lots of stuff around under /Library (or worse, if they had a .pkg). Then you have the Frameworks complications, plist-caching hell... Just because Mac apps don't use a central registry it doesn't mean they are so much better than Windows ones. In comparison, apt-get is not bad at all: you install and uninstall anything with one command and --purge gives you you decent guarantees that it will all go away, including config files.