My landlord does this. Every email, no matter how mundane, ends with an all caps warning that the information in it might be privileged or confidential, etc. and how I'm to delete it posthaste if I was not the intended recipient.
Like … I don't take orders from an email. You're basically begging to be uploaded to the Internet like that.
I mean, these are the same people who nickel and dime tenants for repairs the owners are legally responsible for, expecting to get it through bluster.