Email Addresses Public on Events

Email Addresses Public on Events

With the sensitivity around mails. I find it puzzling that its so hard to restrict some users from viewing emails on the crm. I have quite a few contractors who work for the company who does not have access to contact page information.
However, when i assign an event to them, they can always see the customers email address. I call tech support who suggest de-linking the related in the Fields & Link Permissions section. This worked, that is until I fould out that as soon as the user edits the event to attach a document etc, that event is de-linked from everyone and is no longer linked to the contact etc.v Please help.

See video below.
https://vimeo.com/user15535753/zoho-crm-public-emails