[dsr_]

Don't bother. If you collect email addresses, it's PII and someday you will have to account for that.

Instead, give them a searchable FAQ or a wiki and an email address to write to for support. Connect it to a ticket system that autoresponds with a ticket number.

(then you added your second paragraph while I was writing this.)

[londons_explore]

I get users to email a personalized support email address.

Eg. [e-mail]

The support team can figure out which account or anonymous cookie saw that email address.

It's a handy way to still communicate directly with users while holding as little PII data as possible about them.

[gen220]

This is really clever! Thank you for the idea.

[tapneal]

We're hoping to test an email password recovery option after the account is set up. It builds on the idea of getting more information after commitment.