Dislike of muzzles!

Out on a walk this morning, Lennon met a lab wearing a muzzle, the muzzle was because being a lab it ate anything & everything on walks! They were both off lead & had a play together and Lennon, as he always does, tried to lick the lab's mouth. When he discovered he couldn't get to the lab's mouth he started trying to pull the muzzle off! I immediately grabbed him coz I didn't want him to bite through the muzzle and he inadvertantly bit me! He did seem quite upset by the muzzle, just wondering what everyone thinks about this behaviour? I know that licking mouths is a sign of submission and I just wondered whether he just got frustrated that he couldn't do this.

I assume it's because he couldn't lick the labs chin properly.

Never seen it before, Chance wears his muzzle and Harvey nor another dog has tried to pull it off.

Has he ever seen a muzzle before or interacted with a dog wearing one? Maybe he was unsure about what it was and it confused him or something?

I think a muzzle on either dog upsets the status quo somewhat - must look very strange to the non-muzzled dog.