Why? Just use different address for the legitimate service and whitelist it. If an address is out there on some spam list, you'll be getting spam to it eventually.

I have different rules for different addresses. Public e-mail adresses and e-mail adresses that are meant for online services. Public ones are permanent and filtered and mailchimp and similar don't get to send mail there. The other type of address is whitelisted and disposable. Everything ends in the same mailbox. Works like a charm.