Letting a pup have a few bites of corn isn't a horrible idea provided she's not allergic, but I wouldn't recommend doing this on a regular basis. The issue is not with the kernels (which can be a dog food "filler" item), but cobs are very dangerous for pets — they can cause intestinal obstruction if swallowed! Make sure to hold on tight while she nibbles, and throw it away in a pet-proof trash can after the snack to make sure she doesn't go in for seconds.