Liability for the loss of a pet, even if at fault, would be minuscule compared to injury to persons. In my travels, usually dog bans are for one of three reasons: they can startle horses, they harass wildlife, or their owners leave pet mess, so my bet is that it’s one or more of those. It seems excessive to ban them from the cars, but my guess is it’s easier to enforce the ban that way.
I would have say it is because of the wildlife. When i lived up there my dog used to chase after the mountain lions, deer and boar whenever he saw them. So I'm thinking maybe it's a liability thing. Like if your dog went after the wildlife and got hurt they might be liable.
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