Yes, I would take care of them if they were still alive, and being not fenced dogs they probably would be. I think this would be more focused on dogs animals that can't get to food and water without the owner.
Some notes from the comments - I didn't find any stats on the frequency this situation is applicable.
"We've had quite a few requests for a generic "my pet(s) are home alone" card but haven't made them yet. Soon though"!
"I work for a pet nanny service and this might be a neat thing for me to give to potential clients during a meet and greet. With that in mind (if you are currently taking suggestions), have you considered a bulk order rate"?
"Certainly! We offer bulk discounts as we supply cards for a number of vet hospitals and rescue organizations".
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I just updated my emergency contact info on my phone with "My pet is home alone, please call my emergency contacts."
It's also a good idea to have an emergency sticker on your front door or on a window in case of fire. Most fire stations will give you one for free as well.