well, I've been for the last couple of years, and it's cheap.
I think they're winding you up.
large bottles (probably holds 6 pints) of water were costing me around 3 euros, so it's not a big issue.
something like robinsons orange squash may cost a bit more than in the shops here, but not a lot more, and if you;ve paid out for an all inclusive holiday I really wouldn't worry about a �5 of squash over the 2 weeks.
you'll probably have bottles of water in your room anyway, and will get them free at lunch, dinner etc too.