Loca used to try to grab little dogs during our walks. I didn't muzzle her, but I always carried one with me just in case. I was vigilant about looking for little dogs. Once I was talking to an old lady that had a leash, little fuzzy dog with her. Loca lunged. I pulled her back and just kept talking like nothing ever happened
I've you have a car, there is a nice dog park in Georgetown. Nobody goes there during dinner time. That might work for you.