I love the people who feel the need to inform me of how big Sierra is going to be too.
Typical scenario:
Moron: What kind of dog is that?
Me: A Newfoundland
Moron: Oh! You know how big they get right? Are you sure you want a dog that big?
Me: Yes, I'm well aware of how big they get. The size is one of the main reasons I chose her and yes, I'm quite sure I want a dog that big. But thanks for your concern *insert sarcasm*

And when she was a puppy - "She's awful small for a Newf". My response started to be to explain politely and then I got sick of being polite and I started responding "Well of course she's small, she's still a puppy. She still has growing to do. You weren't born full grown either."
When I still get the comment, I usually give the web address to the AKC or Newfoundland Club of America and tell them to read the breed standard because she is actually slightly taller than the average height for a female.
Then her drooling.
Me: Be careful, she drools, here is a towel. (I always carry one)
Moron: Oh It's ok, I don't mind.
Then a second later...
Moron: Eww, she slobbered on me! How disgusting! How do you live with that?
Hey, I offered the towel...
And my personal favorite:
Because she doesn't have her shaggy coat right now, everyone thinks she's an oversized Lab.
Moron: What a beautiful Lab!
Me: Actually she's not a Lab, she's a Newfoundland.
Moron: I know a Lab when I see one, I've been breeding champion Labs for years.
Me: I don't know what kind of Labs you are breeding, but if they look like my dog, then you are not breeding any Lab recognized by the AKC. I know what kind of dog I have, and she's a Newfoundland.
Moron walks away shaking his head because apparently, I am stupid and crazy to be calling my "Lab" a Newf.
And this drives me nuts: I was was walking Sierra through a dog park and some woman (with a little fluff ball type of dog) ran up to her child and yanked him away from me and Sierra. We were a good 10 feet away.
Me: Excuse me maam, Is there a reason why you pulled your child away from my dog?
Crazy woman: Well look at the size of your dog!
Me: but did she make any type of aggressive or threatening movement? I'd like to know so I can stop that kind of behaviour.
Crazy Woman: No she didn't but she's huge and I'm just protecting my son.
Me: Just because she's big doesn't mean she bites.
Crazy woman: Well, small dogs don't bite!
Me: Is that why your dog is snarling at me and mine is wagging her tail?
I never used to be rude to people and defending my dog has really changed me!
