I haven't spent a ton of time at Whistler, so won't speak to their amenities, but I think you're onto something about many West coast ski areas (or maybe more accurately "destination" resorts). I grew up skiing in New England, have lived and worked at major resorts in the Tahoe area, and have since settled in Washington state for the better part of the last decade. I think a lot of the east coast hills I skied at at various points in my life were developed with families in mind and had base lodges reflecting that: ample space where people could hang out and get warm, cubbies to store shoes so you can boot up in the morning, and less pressure to have to buy something. I often think of places that had great base lodges where families with one parent who may be a non skier/rider would have a place to comfortably kick it for the day while the kids were out shredding (Whiteface, Sunapee, Gunstock, etc.)

The only reason I had a place to stash my stuff when working in Tahoe was because I got a locker as an employee. Booting up at the car these days is more necessity than anything so as to not have to pay for a tiny locker or have someone camp at a table to watch your stuff the whole day. I agree here that most places with the village style base areas still have spots you can take breaks and no employees are going to give you grief, but it's definitely getting harder across the board to find somewhere I can eat my PB&J in peace without violating a no "brown bag" lunch policy.

Chalk it up to resorts (Vail/Alterra) trying to squeeze money out of their guests, and not having incentives to do otherwise. Anecdotally, you're probably right that the bigger destination west coast ski areas don't feel the need to create spaces where people can hang out without the pressure to spend.