Replying to Skiing with a Backpack??

So I'm going to Japan this season for a few weeks /claim......

and I'm wondering if I should get a backpack to ride with. Now I normally don't ride with a backpack in Aus cause there's no need really with my car at the base and in Japan our accomodation is within like a 5 minute shuttle ride if I absolutely forget something and need to go back.....is there something I'm missing when I see all these Japan edits with people with backpacks on?

Now as it's my first trip over I'm staying inbounds and although I think it would be sweet to have the k2 pilchuk or something like that with the shovel and probe I have no experience at all with that stuff so am thinking that there's no point getting it.

Now I have a Lowepro Sport 200 which has a compartment for my DSLR (it's a holiday I want to take photos) but was a bit apprehensive on the waterproofness of it.

Also what do people take in their backpacks? Lunch?

Thoughts?