breeding a dog for work is one thing???
It's not different.
Yes there are already plenty of pet breeds available, but there are also plenty of breeds available for work.
I find that argument quite ridiculous.
Either you can find the characteristics of a cross in a purebred or you cant, it's simple as that. Whether it is a working breed or a pet doesnt come into it at all.
You cant use the argument when it suits....to me, that indicates that it is purely a bad attitude against "oodles" and nothing to do with crossing at all. You either agree with cross breeding or you dont, you cant pick and choose when you think it is OK (ie. working dogs are fine, oodles are not).