Maybe you smell like sausage haha?
Actually I noticed that too, stray dogs and cats like to come over when I sit down at such places, in fact some cats even jumped onto my lap. I think it has to do with the eye contact you make with them and your tone of voice.. if you give them the correct "look" and get their attention, they might come over hoping to get some food and attention from you... these poor, neglected animals really lack of love, if only we can find homes for all of them
