"A dog who is instigating by being rude to your dog is looking to start trouble, " Mr. Oguss says.

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The owner estimates that the cart could sell 50 units an hour with no trouble, a dog and soda every 2.4 minutes.

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Dave Eales, landlord of the Smoking Dog, said he had anticipated trouble might occur and had told the Lyon police as much earlier this week.

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Local authorities there are able to issue dog control notices at the first sign of trouble in an effort to deal with animals before they become a danger to the public.

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