I get it all the time. Earnest is a Lab/Dane cross, I know for sure, I saw both his parents. People tell me he can't be Lab because he's not black, and he can't be Dane because he's "speckled" (he's a merle). So part of him at least has to be Aussie or Sheltie, because those are the only merles anyone can think of, despite the fact that he has NO FUR- not even a Lab coat, he has the slick Dane coat with an almost naked belly. (And he's 150lbs!). I don't mind so much when they ask if he's part Catahoula, at least his coloring and shape could suggest it- I just hate when they want to "correct" me when I tell them what he is. Sometimes if I can sense the person asking already has an attitude I tell them he's a Lochbuie Lurcher imported from England and he cost me $5,000. Boy, are they impressed- one lady said "Oh, yes, a friend of mine has one, yours is a fine example of the breed!!! LOL!
Phyfe is even worse, because I don't really know for sure, but as far as I know he's St. Bernard and OEM, that's what his orignal owners told the humane society he was, the people I got him from said Golden and Dane (NOT). Some people (I guess ones who have never seen one) think he's Leonburger, they come up with all kinds of guesses. My "pretend" breed for him is Cane Garouf- although he's big, he's not THAT big, but he does look surprisingly like an engraving from the middle ages...