[bsder]

The real problem is that you are all on the same email provider.

If we didn't have a monoculture in email providing, this would be far less of an issue.

[lazyasciiart]

Do you think yahoo and Gmail are the same email provider?

[zargon]

Enough people clearly do -- they think that all email addresses end in @gmail.com, even if they check their email at yahoo.com. Because we have an email monoculture.