I read this the other way. In the rule book in the box (which reads different from the one currently downloadable on BGG) "When picking up ingredients, you MUST pick up all viable chickens at once as a single pick up action".
This actually added fun to the game because it adds a press your luck element. Once I was getting greedy and looking for something specific, and I flipped over a chicken and had to take it instead of the ingredient(s) I really wanted to take.
If you choose to pick up chickens you must pick up all of the visible chickens as one of your pick up actions.
Sorry for the confusion.
I just got this game and still confused: so if you choose to take chickens you take them all as ONE pickup - isn't that a good thing? You're getting multiple ingredients for the price of one pickup action (and you still have a second)?