Of course many people feed their dog the occasional "no-no"; however, I don't recommend feeding either milk or garlic as BOTH ingredients are on several lists I've googled as being considered toxic to dogs. One such article is:
http://http://www.peteducation.com/a...articleid=1030.
I recall my former dog of 14 years eating chocolate on the rare and accidental occasion; however, I would NEVER encourage anyone to feed their dog chocolate as we all know it CAN KILL YOUR DOG! For those who tell you garlic or milk is not going to hurt them or "their dogs would have been long ago dead", please disregard their comments. They are DEAD wrong, and I wouldn't listen to anyone who encourages me to feed a food known to cause illness and/or death. Of course your dog may go "crazy" for a taste of garlic or milk or ice cream or chocolate, etc. But just because your dog likes it doesn't mean it's ok for them to eat/ingest.
I suppose a little garlic or a couple of grapes won't do any real harm, but who wants to take that chance? I know I don't. Regardless of those who feed food with garlic in it fairly regularly, I DO NOT recommend it!!!