The problem with selling broccoli is the cost is tangible and the benefits aren’t. Broccoli buyers maybe see the benefit when they get their annual blood work done. Broccoli buyers also might enjoy broccoli if they incorporate it in a recipe that masks flavor and leverages texture. But broccoli isn’t what people want.
The best chore chart in the world solves the Tragedy of the Commons. The Tragedy of the Commons describes a situation where Roger, Sally, and you don’t maintain a shared item because you each only partially benefit from your individual effort to maintain the item. As a result, the shared item tends to fall into disarray. The Tragedy of the Commons is why your bathroom is never really clean.