I think ESET lacks one very important feature which also affects computer security a lot, without password protection in Activate your product... window other computer users can modify your product key. I think that once password protection is defined through ESET settings it should also cover the whole product, including Activate your product... window.
My suggestion is that when you click Activate your product... link it should ask your password.
I know that other users can not see the password when you activate your product using Username and Password method, but in my opinion other computer users should not have a privilege to open this window in first place.