The dog at the Stop and Rob

Stop and rob being what we call the one and only convenience store we have around here.
There's a really emaciated looking dog that's been hanging out there for as long as I can remember. She's a hunting dog. She's not super friendly and she wears a collar. In this part of the country a collar means hands off. Even if I ignored that unwritten rule, I couldn't bring her home. My SO simply wouldn't allow it. If I knew who owned her I would report them somehow; but it's in the county, not within the town limits and the county doesn't have animal control; only the town does. We also don't have anything that remotely resembles an SPCA.
Anyhow, when I stopped to get a paper there today I did what I normally do....I bought her a hot dog on a bun. After I layed the hot dog down on the curb for her the clerk sticks her head out the door and says, by the way that's brings her total of hot dogs today to 6! and two honey buns besides!
The clerk and I talked about the dog. She says that the dog gets plenty to eat there, even if it's not the most appropriate of foods. She's obviously got something wrong with her that she eats that much and still looks starved. She gets at least 5 hot dogs a day, plus other stuff and the clerks give her all their leftover pizza fixings at the end of the day.
I'm at a loss as to what to do. I've thought about not feeding her hoping she'll go home (the clerk knows she has one) to eat dog food; but even if I don't feed her I'm sure others will. I've also thought about carrying a small container of dog food from home in my car to feed her instead of the junk food, but she'd probably turn her nose up at it after all the goodies she's used to.
This doesn't make the first time I've been made a fool of by a dog! :|