That's weird. Maybe it is a glitch.
If you time travel, maybe move forward a few days and see if it changes. Maybe it is not the same for everyone? but it seems to be.
Hopefully the next time you open your game, yours will be covered.
Unless I'm mistaken (it was a long time ago) I have a memory of seeing someone with holly bushes completely covered in snow, as in with no berries showing through. Mine have the snow and the berries showing through. Is that what you're talking about? Could there there variants of holly bushes or something?