I'm noticing that when Drecko eat Mealwood (although it appears to be similar with Pincha Peppers) They will eat a plant down to 0%... and just not stop. They keep fruitlessly trying to eat more from the same plant.
They eat, they eat, and they don't seem to get full. This gets out of hand fast if you have multiple Dreckos trying to eat from the same plant. In the picture below, I have five Drecko all trying to eat from the plant on the right, and they're all ignoring the plants to the left. (except for paul, he's a clever one and came from the left instead of the right.
Make a big pen of drecko Make a small patch of plants (mealwood will suffice) All Drecko will only eat from the edges of your patch, won't move on until full. Not even if the plant is empty.