I'm always baffled by the fact that a pretty good percentage of the obese dogs I know are owned by incredibly fit, active people. As for my own public interactions - I don't change much. There isn't much I do that might come across badly to people, I don't think. I do lightly smack/kick Gusto when he's tugging, including on the leash, but I'm usually chattering at him and play growling back, so I think it comes across as the game that it is. I do talk incessantly to my dogs when I'm not in public, including having voices for them, and I make an effort to not do that in front of others - and sometimes forget. Oh well. I'm okay with being the crazy dog lady.