People tend to check in during these times:
America runs on Dunkin', and DD Foursquare runs on You.
Damn good iced coffee
Try the Doughnuts - :D
I have not had any problem with the free donut. Some don't know about it so I explain and I get it free. When the boss is there there never is a problem
Check you're bill. They will charge you for the free donut when u unlock on Foursquare. I have argued twice now. No bueno!!!!!