How Much Will People Put Up with from Their Dogs?

I happen to have the same name as another dog person, who lives in eastern Canada and works with aggression. Apparently she does not have a web presence, as people stumble onto my web and think I'm her. So I get questions. . . actually, usually more like pleas for help. . . about aggression problems on a pretty regular basis.
The latest one was from a woman with three dogs, the last being a recent addition. The first two dogs are attacking the third dog, who is disadvantaged (I think blind, if I remember correctly). There have been punctures, and the last time the woman was bitten (severely, as she put it) because she got between two of the dogs. She says she can't get rid of the new dog because he would be put down, and wanted the other Cheryl Smith to work with her one-on-one.
Certainly face-to-face work is the right idea with a problem such as this. But since she found me rather than the person she wanted, she's still without that help as far as I know.
So just how much will people put up with from their dogs?
I owned a psychotic Springer mix when my roommate adopted a terrier mix that had never lived anywhere but on the streets. The two were a disaster together. The terrier wouldn't submit to the springer, and if I wasn't on constant red alert, they attacked each other with vigor. We ended up with some expensive vet visits. When we had company, we had to put at least one of the two dogs away in a closed room so they couldn't fight. We couldn't relax in our own home because we had to be on the lookout for trouble brewing. But we didn't even consider getting rid of either dog.
I see two extremes with this problem -- the people who immediately ditch one or both of the dogs, and the people who hang in there through everything, paying the bills, often getting bit themselves. It's an odd display of our devotedness to our dogs.