i get your point but imho carrying both is a bit too much gear for skiing in a relaxed way, there's a point where you need to decide how far you want to go in terms of safety gear ...
you could say the same about bringing rocket flares, satellite phones, bivy bags, portable stretchers, climbing gear, etc.
you just don't bring em out on the average skiday because they're too much of a hassle
+ are you really going to ski every line with the snorkel in your mouth ?
or do you think you'll have the time/reflex to pull the airbag AND stuff the snorkel in your mouth ?
i hardly doubt it ...