I've certainly never bothered carrying anything food/drink. CPs are approx every 10k.
All have juice; some have tea & coffee as well.
Food on offer varies: lots of cake, sweets, chocolate, sandwiches, malt loaf. If I was being really picky I'd say there was too much sweet and not enough savoury. But I'm not picky. It's all "fuel".

The dinner at the end is very welcome too.