[sinatra]

Keep in mind that catch-all accounts usually get a lot of random spam. If you're using this domain to signup for various services, at some point, spammers will become aware of it. And, they'll start sending a lot of spam to (random string that spammer comes up with)@your-domain.com.

[PinguTS]

I have catch-all running for a few years now, but no real spam problem. Maybe due to the fact that greylisting still works pretty effective. Most of the spam I receive is on my GMX including the email address I never used for sign-ups of any sort.

[gohrt]

This is why mail hosts and MX registrars offer spam blocking.