Originally Posted by 1sweetwater!
I did not add any other repositories and only have them running dpkg from grub menu during boot.
Well, this is a bit beyond my knowledge but I do know that the grub shell is not a Linux shell. (though it does have a very small subset if bash commands.)
Chances are that the gpg keys are not even available in that environment.
Like I said though, if you're certain the packages are coming from the right place, you can take a chance and install them without authentication. It's really your call and your own judgement is the best guess here.
They main reason for the authentication keys is to prevent a hacker from spoofing the repository and tricking you into installing tainted packages. I feel that the risk of this is fairly low for most private machines using there own home connection. However, the risk is much greater using public Wifi where a hacker could setup a "free" access point and use it for a "man-in-the-middle" attack.
It all comes down to how certain your are that the packages are legit and from a trusted source. If you have any doubts, don't install without authentication. If you're certain they're legit, then it's okay to install without authentication.