Honestly there is no logical correlation between putting a snake in a bathtub with water and going back on feed. Maybe your snakes were just very hungry this time around. Maybe you presented the prey items differently.

I don't think it has anything to do with a bathtub full of water though.

My best guess so far is that the water covers them on all sides and makes them feel secure. If that is the case, there is probably something wrong with your home enclosure setups.