+1. I also use *@mydomain.com feature in G Suite, and it's very convenient to understand which companies sell/pass email databases to others w/o my permission. In some cases, you need to reply from that "aliased" address -- in this case, I do go to the Settings, add an alias, got a confirmation code, and confirm it. Then this new "address" is available in GMail in drop-down "From:" menu when you write a new email.

username+anything@mydomain.com is also a useful feature (as well as u.s.er.nam.e@mydomain.com – dots are all ignored in GMail; some services don't allow "+" in email address field, so you can use finite number of variants with ".").

These little tricks make GMail convenient for geeks :)