Player-placed snow layers melt

What I expected to happen:
Snow layers placed by a player don't melt, just like leaves placed by a played don't decay.

What actually happened:
Snow layers placed by a player melt.

I can imagine this being intentional, but than there is still a bug, which is that 8 snow layers placed on top of each other don't melt. Do I need to create a separate bug report for that if this is intentional?