Dave Hanson wrote: Carrying a bottle of water around all the time in the UK is just fashion.

As with many things this all depends on context. When I worked as a volunteer steward for folk festivals (you know, the real folk police) I always took a small bottle of water or cold tea with lemonade on my duties.

If I'm sitting around the house all day or nipping to the shops there is no need. Intensity of hangover can increase the likelihood but I'm having a sober month right now so no bottled drinks.