Morrisette said:If there's an M and S food place in the airport their water is quite cheap.
Or take an empty bottle in your bag and fill it up at the water fountain (if there is one) in the loo.
The no-liquids rule is the biggest scam of all these anti 'terrorist' rules IMO - and it's got some stiff competition - you have to look at who benefits from this rule - is it me? No. Is it Mr. Evian and Mr. Vittel?? Ohhhhhhh yes....I reckon they sponsored the whole thing. You have to follow the money.....
Like you say, why is water more of a danger than sandwiches? Plastic explosive in a bun is surely just as likely as a baby milk bomb, or whatever it was supposed to be.
Looking for a 'beard the size of a fist' is usually a good indicator of whether there might be intention.