Retailers have it made with Valentine's Day, Mother's Day and Easter usually falling in the first quarter of the year.
I'm no retail psychologist, but I wonder if they deliberately get the stuff for each season out very early in an attempt to make people feel pressured - even though they claim it's to provide a choice for those (who, granted do exist) who like to have everything planned well in advance.
Even if they don't expect to sell that much Easter stuff in January, the fact that it's already been out for a few weeks can make customers fearful of how late they've apparently left it - and concerned that others will beat them to get the stock and it will all sell out. Plus, with things like Easter chocolate, I bet loads of people do plan to buy it early to be well organised - then eat it/give it to the kids early and have to replace it several times!
I'm just thinking of the tactics used by a certain well-known sofa company (among others), that has constant 'sales' on. It obviously works for them, otherwise they wouldn't bother keep making themselves look a ridiculous laughing-stock by urging customers to hurry and buy now as the 'sale ends soon'.
Then again, I'm aware this may be controversial, but I see all the perfume adverts for bottles costing £50+ and not a single one I've seen has ever told me what it smells like, much less how it can possibly be worth such a high price for such a small amount of liquid; so I suppose retailers know exactly what they're doing!