I'm assuming you either mean on TV ads and such or at a ski resort.
- On a TV ad, they usually use shaved ice, with very expensive large machines that are fed ice blocks. This is used because it doesn't require the right temperatures and conditions to make real snow and it is much faster.
- At a ski area, it is not even artificial snow. The snow created is completely real and the difference is so subtle you can hardly tell. The main difference is it is a bit denser and melts slower.
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