What if the drone has a 2-3m acuracy of the position? At least in ski resorts the bystanders can immediately rescue the person. Off tracks, it often happens that 1 person is aside of the snow corridor.
That level of accuracy would be hard to achieve. Most radio signals (eg. BTLE) don't travel well through water (eg. snow).
Additionally, if you've ever dug someone out in the field (or practiced doing so) it takes a lot of effort to move snow. Being within three meters isn't good enough.
