Dream Zoo Starve some Animals for more Gold

Okay. I just got an idea. First, let me lay down some premise.
1. Washing animals gets more Coins than Feeding animals
2. Washing animals at a high level habitat (basically what level you get that habitat) gives you more Coins.
3. Hungry Animals (the ones with the food icon above their heads) will never die (so far, it's been over a week and my hungry animals are still there)

Also, I have this hypothesis that there will always be (barring any cooldowns) that there game/server will give you something to do in the game, like washing or feeding animals. Also, I hypothesize that you can have as many dirty / hungry animals as there are animals.

So, my idea is to Wash all the animals you can, and Not feed the lower level habitat animals. In that way, only the Higher Level Animals will be Dirty, and needs to be wash, and therefore, more gold per wash.

I know for sure that the Hungry Animals persist when you shut down the game. However, I don't know when the game actually saves this info. Sometimes when I crash, some of the new Hungry Animals are no longer hungry.

So what I'm currently trying to do, is to get all my animals hungry, then just feed the higher level animals to get maximum gold when I do interact with my own zoo.

Weird game strategy I know, I wonder if it'll work out that way.