Sorry, but I don't see the issue with this scenario.
If the site-owner is stubborn enough to not delete accounts for people whom have left the guild -- so be it. He'll have a cluttered and outdated site that he's paying money to keep going.
Other than having access to your email address and other info that you signed up with, he doesn't have any other information. He doesn't have your password or anything of that nature. If you want to be extra cautious, login and change your email to something else that's non-existent.
And I'd prefer it to stay this way for users not to be able to delete their account. A compromised account could be disastrous with wiping out someone's DKP history and all of their info. Giving people the ability to delete their account would do more harm than good.
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Followers of Nobility