Fun DD fact: If you actually eat donuts, save your receipt. On the bottom of each receipt is a survey code that gets you a free donut with "purchase" of any medium beverage.
I remember last summer I had a ton of free coffee promos to use. 1 day per week I'd walk in, get my free medium iced coffee, present my coupon from the week before, get a free donut, ask them for a receipt, then rinse & repeat for like 10 weeks
I'll look back on that 10 years from now & still say the 'Beetus was worth it.