Why you probably can’t be bothered with hydration…
It’s completely understandable, drinking water when skiing seems like a faff that on the surface, doesn’t even really seem that relevant to how much enjoyment you'll get from your holiday.
If you’re a good skier, maybe you want to feel as free as possible on the slopes and not weighed down with kit like you're going on a camping trip.
Those newer to skiing already have enough to think about and if you're going to spend a couple of days falling over a lot, you probably don’t want to be falling on a lumpy rucksack.
In both cases, you're in a cold environment so it seems quite unlikely that you’ll be sweating much anyway, so no need to drink water, right?