I do try to think about the holidays quite a while in advance, because I like to make gifts. It's no fun to be scrambling at the last minute. That's what destroys a holiday for me. So enjoying the "prep" as early as possible, just enhances the holiday for me. Nope, doesn't bother me at all for marketers to give me ideas well in advance of a holiday and to be able to purchase craft items at a discount.
In fact, I just had a PM from a board member asking me about ornaments that I posted in May.
I often get ideas for cards and begin making Christmas cards in January before the Christmas Glow has faded.