I have a cat. Zena will stick her nose up the cat's butt at every opportunity. I also have stray cats that leave poop in my yard overnight. Zena finds it and eats it readily the next morning. I try to watch her but she is sneaky. So, no puppy kisses on the mouth in my house. Yetch! Would you lick your private parts, then kiss your kids? Would you lick your partner's poop shute, then kiss your baby? Ewwwwe! I visited a strikingly beautiful young woman at her home one evening. She had dog named Whiskey, a border collie mix. We had a nice dinner and conversation and the evening was going well. Whiskey was in his bed doing some "housecleaning" for the better part of the evening. We had cocktails after dinner and to my shock, amazement, and disgust; my hostess called Whiskey over to her lap and shared her drink with him; let him drink right outta her glass. Lap lap lap slurp slosh slosh slurp. OMG! Suddenly it got very late and I had to leave. Never saw that lass again.
I understand why dogs like to lick their owners on the mouth. It is feeding instict to get the parent dog to regurgitate their "kill" for a meal. But since it is not applicable in my household; no kisses or licking on the mouth. Nope! None ya! Nada! No way!