It appears that when you remove a domain or a subdomain using the web panel (https://panel.dreamhost.com/index.cgi?tree=domain.manage&), then the files on your plan are not removed.
Wouldn't it make sense to remove the /home/username/domain/ directory tree when removing the domain? At least, during the domain-removal confirmation, provide a check box to choose whether you want the disk files to be removed along with the domain, or keep the disk files even when the domain is removed.
Luckily I've learned about the command "rm -Rf -*" or else it would be a real pain to clean up after the subdomain which I just (thought I had) removed.
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