The Pet and Thrall Hunger System has indeed been adjusted since March. There were parts being adjusted and removed in little batches and gradually, after the decision to replace the initial system with the new one. How it was communicated in the patch notes was not ideal and we apologize for that.
Here is how it currently works:
The Hunger System (the need to constantly feed thralls and pets) has been removed. Because it wasn’t really what we had envisioned and while some players liked the system, many more perceived it as an unnecessary grind.
This is the reason we decided to remove it and replace it with a system that essentially works like the building decay system. Your thralls and pets get placed on a timer from where you place them and you can reset that timer by being in the game and close to the trall/pet in question. If you let the timer run out, they will die and disappear.
They will still take food to gain buffs but as you noticed they will immediately eat all food, no matter how much you give them. The pet/thrall will then gain the buff and should display an icon when the buff is active. The reason all the food you give them disappears is because the feeding areas or their inventories linked to feeding them are not supposed to be used as additional inventory.
We’re looking to get the feedback on this system more clear and possibly some additional cues on timers.