If I may tell a story here: our neighbors love our dog buddy. When we first purchased our home Buddy was tied up when we could not keep an eye on him as we didn't want to upset our new neighbors. After many visits with our neighbors and them convincing us that it was ok for Buddy to come over to visit them we laxed on tying him up. At first it was great he'd go over say hi, get a treat and return home. Eventually the visits got more frequent and longer and as you know once a dog know's he's going to get fed that's where he's going to be. Buddy is a shepherd/lab mix 130 pounds. More than once we were out looking for him as he did not come when called as you can imagine we were frantically searching for him and this is when we found out he was being let into their house. Buddy is a smart, loyal, and excellent mannered dog. One day we seen them allowing buddy to get up on the picnic table to get a treat and to us this was unacceptable because at our house we can set a Steak on the end table and he would never touch it. So it was time for an intervention, the first of many we asked them to limit treats and to send him home after a bit so we didn't worry, and to not let him into their home. Our neighbors are also elderly and one is partially immobile and we were careful not to hurt their feelings as we did like that they loved our dog but they were killing him with food, their form of love. We grounded buddy many times, reinforced the no leaving the yard, chained him up when we weren't devoting 100 percent of our time to him and the neighbors knew he was not allowed over there as they were not following our rules. Things got better but it took 2 years and about 15 pounds which he has lost since the bad feeding habits. We just lost our neighbor "Bob" Dec 22 and it was very devastating to me but it has been horrible for Buddy he still goes over everyday to see Bob, but Bob doesn't meet him at the door anymore, there's no treats or ear rubs, there's no more sitting next to Bob on the picnic table and providing his loyalty, protection and love. Our dog brought us closer to our neighbors and I doubt we would have been such good friends if it wasn't for buddy.My peace is that these last two years Bob has had someone who visited him everyday and showed true affection for him ( the treats didn't hurt). His wife still works and buddy is let out 2 specific times a day she she eaves for work and wen she comes home, she has a treat in her pocket for each meeting and I like to think he's sending her off with a smile and now more than ever she at least has someone waiting for her when she comes home at night. My advice reinforce your rules they will eventually get it, might take 2 months or 2 years but it will come.