To get the free dessert, one must order an entree and a salad  But anyone who orders either an entree or a salad can receive a free soft drink
Thus, anyone who is not eligible for a free soft drink is not eligible for a free dessert
To grow good azaleas, one needs soil that is both rich in humus and low in acidity. Anyone who has soil that is rich in humus or low in acidity can grow blueberries. So, anyone who cannot grow blueberries cannot grow good azaleas.