I have found that as long as you leave water accessible that it gets drunk - also if they go outside they probably drink rainwater or pond water.

(I also think that they drink toilet water too - uck)

I mix my wet foods so that they don't get a run of only one brand. Also I find that even though they turn their noses up at teatime, if I leave it out during the night by morning it is all gone - the cat fairy comes in the dark hours apparently and scoffs the lot.

I also give raw or cooked poultry.