I would be angry too. Whenever I see people letting their dogs off the leash in the park, epsecially near the playground, I get upset. I like dogs and I understand that people LOVE their dogs, but have some respect for others! I cannot take the risk that a free running dog will end up hurting one of the kids in my care. My mum got knocked down by a dog years ago on a university campus (I was with her)...it came running and hit her in the bag of the knees so she fell. She still suffers from nerve damage as she fell right on her tailbone. There are dog parks for dogs to run free....or out in the country. In the city, they should be kept in fenced yards or tied up and kept on leashes. I would be livid if I were you and I would have to report to the city as it is too much risk having big dogs running loose with your daycare right there. Good luck!