Snow is ice. And a bunch of weird material science happens when snow gets compressed, melts a bit in the sun and freezes again (which is afaik how glaciers formed in the first place - how else did the ice get there?).

You actually want to have an ice sheet on the slope when you go skiing. Otherwise the snow would get pushed away from the skis after a few swings and the ground wouldn't be covered anymore (ruining the skis of the people that come after you).

I remember a crevasse forming onthe slopes of the mountain I grew up at when I was 9, I think. Obviously, it was only about 1.5m deep, but it was a clear tear in the snow sheet and you could see the grass underneath the snow.

Skiing on glaciers has been done since the invention of skies.