I really do wish people would understand the term 'Mongrel' before using it, you just look a bit thick using it in this way, and at best snobby.
A Mongrel is a dog no a dog of no definable type or breed and isn't intentionally bred. If a Poodle and a Spaniel have been intentionally bred, no matter the twee name given it's not a mongrel. It's also got quite an offensive connotation so you're both rude, and wrong, and lots of people believe they're using it correctly because there are some 'experts' who use it, but it is designed to be impactful and offensive and suggests that a dog which is not purebreed is inferior, when this simply isn't the case.
For example, I do a lot with Guide Dogs for the Blind, and a large portion of the dogs they breed, are not pure labradors or pure golden retrievers, but a cross between a Labrador and a golden retriever to give the best mix of traits to make suitable guide dogs. They offer more information about the breeds they use, the way they are mixed and why on their website if you're interested www.guidedogs.org.uk/about-us/national-breeding-centre/what-the-national-breeding-centre-does/our-breeds Crossing breeds is a legitimate way to breed dogs with specific traits and done responsibly isn't a problem, and isn't a mongrel either.
Don't judge people for buying a mixed breed dog that will fit into their lifestyle well. Judge the people who are buying dogs with breathing difficulties or who are abandoning their dogs as strays or selling them on for profit when they realise dogs are actually quite hard work. Spend your time worried about that instead, it's more useful than calling people's much loves family pets mongrels.
Personally, I have 3 pure breed snow dogs (not huskies though) who all perfect examples of the breed. Extremely stubborn, stupid and do not listen to a word I say. Not sure what class that makes me though.