I can see the breeder point of view on this, but obviously, mine made an exception for me. My kids have also been around animals all of their lives. I also do go a step further with my dogs which has gotten me a lot of flack, but it's what works for me. My kids are never allowed to be alone with either of my dogs nor are they allowed to hold them.
This is not from any trust issue I have with my chilren, more because I do not want any surprises or accidents that I can possibly prevent. I have been told that I'm too strict and being cruel to the kids for withholding the dogs' "affection" from them - but I can say that the four of them all get along great and this is what works for me.
I think the reasoning behind the rule is just to prevent accidents. While you and I may have great kids who wouldn't hurt a fly, they may be more likely to have an accident with a dog than an adult --
But I do think you are right, I wish it could be seen on a case to case basis. I can tell you that my son has some friends that I don't even allow my dogs in the same room as! They are scary!
Sorry for the long winded post!