Halloween In The UK

In the list of money spent on celebrations in the UK, Halloween is towards the bottom with the £776m spent on decorations and scary costumes well below that is at Christmas (£46.4bn), Mothers Day (£2.4bn), Easter (£2.3bn), Valentines Day (£1.5bn) and Fathers Day (£1.1bn) and beats only Bonfire Night (£497m) in the main celebrations so why is Halloween not such a big thing here?  
Some shops do make a bit of a token gesture to flog us Halloween stuff, my local B&M has half an aisle full of cobwebs and spiders and skeleton and vampire costumes but it also has 2 aisles of Christmas things so make of that what you will.
A YouGov found that only 28% of Britons will celebrate Halloween in some way this year with the most common contribution being carving a Pumpkin and watching a scary film to mark the occasion.
I'm not really sure why Halloween has never really taken off over here, some people do make an effort but personally, while not going out of my way to ignore it, i don't do anything to actually celebrate it although i do appreciate the horror films played wall to wall on the TV  but mostly i see it as one of the days, along with Bonfire Night, to get out of the way and then it is a clear run through to my favourite celebration, Christmas.