The inferior snack a co-worker or friend offers you AFTER they eat a delicious, far superior snack right in front of your face. The snack they will choose to not share with you will usually involve large quantities of butter cream icing. You will ALWAYS be miserable and on a diet when said scenario occurs.
Debra offered me some 100 Calorie Snackwell's, but only after she ate the oh-so-yummy chocolate Ele cupcake in front of me. She must really hate me to offer me such a pity snack. :(