Where's our 79 cent reusable coffee cup? Yes, yes, I know if I bring in my own ceramic you'll give me a discount and I won't have the "free" taste of paper in my mouth, but can't we meet halfway? You and I both know I'm too lazy to remember my ceramic every time... and you don't want me to forgo my coffee whim, do you?
Let's make a deal. You give me a thin wall ceramic cup I can use, say 10-20 times around the house and I'll give you 79 cents and remember twice as hard next time to bring my good ceramic.