I make up and use different addresses all the time, for example if I have to give my address to foo for registration I use email@example.com.
Now this brings up something interesting, that I didn't think about in relation to the current catch-all controversy: If Dreamhost would allow this type of mail suffix, that would go a good way toward alleviating this problem. People who use a catch-all for things like the above could retain the ability to have specific addresses for different purposes, and addresses could still be made up on the fly, to a certain extent.
There are two suggestions for this pending. I've long had votes in for both of them. Anyone else interested might want to vote for them as well.
Allow "semi-catch-all" emails like "firstname.lastname@example.org in Mail - Addresses
Allow support for "plus"-style email addresses: user email@example.com goes to firstname.lastname@example.org in Mail - Filters and Spam
Unrelated: Why does this forum strip out plus signs?
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