My sister has a mini shepard and feeds it her food. She can't sit anywhere without her puppy wanting some... OF course she feeds it. If she is at the table, puppy is either trying to jump on her lap, or at least paws on her lap and she will give the puppy whatever food she has. If she is sitting on the couch, puppy will be trying to get the food off her plate itself. Practically licking the plate as she is eating. 
Meanwhile my dog isn't allowed near us when we are eating. I have gotten mad at her and said, maybe you don't mind doing that, but why should everyone else constantly have to block/avoid her begging puppy? My kids can leave their plate at the kids table and not worry that our dog will eat it...
I dread camping with them this summer. Her puppy doesn't need that piece of steak off your plate!
My home, my rules, but her precious puppy. How do I deal with this without a huge fight? Ignore it?
When I dogsit, her dog is tossed outside while my family and I are eating. Period.
Do you have a friend who's dog is allowed to behave different than what you teach? What do you do? How do you deal with it? 