We always have had a no drinks or food out of the kitchen rule. First, it keeps messes down. Second, it helps prevent habitual grazing.
The bathtub idea is perfect. Another thing that you can try is to put down a shower curtain on the kitchen floor. Give her a tub and spoons and cups of various sizes. You might have to do a little mopping when it is over, but it's just a little water!
Take her outside and put her in a kiddie pool with lots of toys. Let her see how it gets soaked up in the grass, rushes down concrete, splashes in the pool.