I'm not really a snake kisser but I have been known to make face contact. Perhaps you could call it really prude kissing :-)
My personal opinion is that most "casual sanitization" praciticed today is rooted in ignorance, mostly ineffective, and driven by advertisers.
My mother worked in the medical field for most of her career. I can tell you that true sanitization is *hard* and it is almost impossible to be 100% effective (She worked on equipment for a "boy in a bubble" case and it is wild how much they had to go through to create a bacteria free environment for him). In the realm of sanitation techniques I would say that slathering on some hand sanitizer is probably about as effective as "early withdrawl" is as a birth control technique.
I also do not agree that it is irresponsible to let your kids kiss their pet snake. Not only are they in far more peril from all the human beings around them - over-protecting children from bacteria is harmful to them.
Anyway, my opinion only. I'm not trying to change anybody's mind. And, certainly, good hygeine practices don't hurt anything as long as their effectiveness levels are understood.