wow! I can't believe someone has enough time on their hands to complain about the sounds of slippers! For heaven's sake!
We're landlords, and when our tenants call and make these types of complaints about other tenants, we just laugh! We always tell people that they are grown-ups, and they should be able to mediate their own situations. Just because we own the property doesn't mean that we are their mommies and daddies, or kindergarten teachers or whatever. And we always tell them that if its a big enough problem, the police are always available to them.

Tony, I think that you should buy the bunny slippers and send the lady the bill.
Dakotasmom, I truly believe that it takes a village, and that people need to feel responsible for everything that goes on in that village. By that I mean that its awesome that you helped that guy out with his puppy and made a difference. I think that even if he was offended at first, actions such as yours really go a long way toward strengthening a neighborhood. At some point, maybe he'll ask you to dog-sit or something. Not that you want to jump at the opportunity to dog-sit a 14 week old lab, but it just creates stronger ties. If you're looking out for his baby, he'll be looking out for yours, too. Ya know what I mean?
BTW, Jade is GORGEOUS! The more Leons I see the more I want one!