I go into our local pet store fairly often to visit all the sad little puppies in there. I can't help but stop when I drive by. I NEVER ever buy anything from the store though, and I'm sure it really annoys them. It breaks my heart to see all the little furbabies behind glass walls looking sickly.
A few months ago I was walking around WalMart holding Macey (muahahaha) and a lady approached me and asked a few questions about her. She then told me she used to work at the pet store in town, and that she had "about three or four of these little babies die because of hypoglycemia."

Well DUH it tends to happen when you only feed your 10 week old dogs twice a day!